diff --git a/etcdserver/etcdserverpb/rpc.pb.go b/etcdserver/etcdserverpb/rpc.pb.go
index 6d0601022..b82d5a201 100644
--- a/etcdserver/etcdserverpb/rpc.pb.go
+++ b/etcdserver/etcdserverpb/rpc.pb.go
@@ -128,6 +128,7 @@ func (m *RangeResponse) GetKvs() []*storagepb.KeyValue {
 type PutRequest struct {
 	Key   []byte `protobuf:"bytes,1,opt,name=key,proto3" json:"key,omitempty"`
 	Value []byte `protobuf:"bytes,2,opt,name=value,proto3" json:"value,omitempty"`
+	Lease int64  `protobuf:"varint,3,opt,name=lease,proto3" json:"lease,omitempty"`
 }
 
 func (m *PutRequest) Reset()         { *m = PutRequest{} }
@@ -390,6 +391,82 @@ func (m *WatchResponse) GetEvent() *storagepb.Event {
 	return nil
 }
 
+type LeaseCreateRequest struct {
+	// advisory ttl in seconds
+	Ttl int64 `protobuf:"varint,1,opt,name=ttl,proto3" json:"ttl,omitempty"`
+}
+
+func (m *LeaseCreateRequest) Reset()         { *m = LeaseCreateRequest{} }
+func (m *LeaseCreateRequest) String() string { return proto.CompactTextString(m) }
+func (*LeaseCreateRequest) ProtoMessage()    {}
+
+type LeaseCreateResponse struct {
+	Header  *ResponseHeader `protobuf:"bytes,1,opt,name=header" json:"header,omitempty"`
+	LeaseId int64           `protobuf:"varint,2,opt,name=lease_id,proto3" json:"lease_id,omitempty"`
+	// server decided ttl in second
+	Ttl   int64  `protobuf:"varint,3,opt,name=ttl,proto3" json:"ttl,omitempty"`
+	Error string `protobuf:"bytes,4,opt,name=error,proto3" json:"error,omitempty"`
+}
+
+func (m *LeaseCreateResponse) Reset()         { *m = LeaseCreateResponse{} }
+func (m *LeaseCreateResponse) String() string { return proto.CompactTextString(m) }
+func (*LeaseCreateResponse) ProtoMessage()    {}
+
+func (m *LeaseCreateResponse) GetHeader() *ResponseHeader {
+	if m != nil {
+		return m.Header
+	}
+	return nil
+}
+
+type LeaseRevokeRequest struct {
+	LeaseId int64 `protobuf:"varint,1,opt,name=lease_id,proto3" json:"lease_id,omitempty"`
+}
+
+func (m *LeaseRevokeRequest) Reset()         { *m = LeaseRevokeRequest{} }
+func (m *LeaseRevokeRequest) String() string { return proto.CompactTextString(m) }
+func (*LeaseRevokeRequest) ProtoMessage()    {}
+
+type LeaseRevokeResponse struct {
+	Header *ResponseHeader `protobuf:"bytes,1,opt,name=header" json:"header,omitempty"`
+}
+
+func (m *LeaseRevokeResponse) Reset()         { *m = LeaseRevokeResponse{} }
+func (m *LeaseRevokeResponse) String() string { return proto.CompactTextString(m) }
+func (*LeaseRevokeResponse) ProtoMessage()    {}
+
+func (m *LeaseRevokeResponse) GetHeader() *ResponseHeader {
+	if m != nil {
+		return m.Header
+	}
+	return nil
+}
+
+type LeaseKeepAliveRequest struct {
+	LeaseId int64 `protobuf:"varint,1,opt,name=lease_id,proto3" json:"lease_id,omitempty"`
+}
+
+func (m *LeaseKeepAliveRequest) Reset()         { *m = LeaseKeepAliveRequest{} }
+func (m *LeaseKeepAliveRequest) String() string { return proto.CompactTextString(m) }
+func (*LeaseKeepAliveRequest) ProtoMessage()    {}
+
+type LeaseKeepAliveResponse struct {
+	Header  *ResponseHeader `protobuf:"bytes,1,opt,name=header" json:"header,omitempty"`
+	LeaseId int64           `protobuf:"varint,2,opt,name=lease_id,proto3" json:"lease_id,omitempty"`
+	Ttl     int64           `protobuf:"varint,3,opt,name=ttl,proto3" json:"ttl,omitempty"`
+}
+
+func (m *LeaseKeepAliveResponse) Reset()         { *m = LeaseKeepAliveResponse{} }
+func (m *LeaseKeepAliveResponse) String() string { return proto.CompactTextString(m) }
+func (*LeaseKeepAliveResponse) ProtoMessage()    {}
+
+func (m *LeaseKeepAliveResponse) GetHeader() *ResponseHeader {
+	if m != nil {
+		return m.Header
+	}
+	return nil
+}
+
 func init() {
 	proto.RegisterEnum("etcdserverpb.Compare_CompareResult", Compare_CompareResult_name, Compare_CompareResult_value)
 	proto.RegisterEnum("etcdserverpb.Compare_CompareTarget", Compare_CompareTarget_name, Compare_CompareTarget_value)
@@ -415,6 +492,7 @@ type KVClient interface {
 	// Txn processes all the requests in one transaction.
 	// A txn request increases the revision of the store,
 	// and generates events with the same revision in the event history.
+	// It is not allowed to modify the same key several times within one txn.
 	Txn(ctx context.Context, in *TxnRequest, opts ...grpc.CallOption) (*TxnResponse, error)
 	// Compact compacts the event history in etcd. User should compact the
 	// event history periodically, or it will grow infinitely.
@@ -490,6 +568,7 @@ type KVServer interface {
 	// Txn processes all the requests in one transaction.
 	// A txn request increases the revision of the store,
 	// and generates events with the same revision in the event history.
+	// It is not allowed to modify the same key several times within one txn.
 	Txn(context.Context, *TxnRequest) (*TxnResponse, error)
 	// Compact compacts the event history in etcd. User should compact the
 	// event history periodically, or it will grow infinitely.
@@ -691,6 +770,168 @@ var _Watch_serviceDesc = grpc.ServiceDesc{
 	},
 }
 
+// Client API for Lease service
+
+type LeaseClient interface {
+	// LeaseCreate creates a lease. A lease has a TTL. The lease will expire if the
+	// server does not receive a keepAlive within TTL from the lease holder.
+	// All keys attached to the lease will be expired and deleted if the lease expires.
+	// The key expiration generates an event in event history.
+	LeaseCreate(ctx context.Context, in *LeaseCreateRequest, opts ...grpc.CallOption) (*LeaseCreateResponse, error)
+	// LeaseRevoke revokes a lease. All the key attached to the lease will be expired and deleted.
+	LeaseRevoke(ctx context.Context, in *LeaseRevokeRequest, opts ...grpc.CallOption) (*LeaseRevokeResponse, error)
+	// KeepAlive keeps the lease alive.
+	LeaseKeepAlive(ctx context.Context, opts ...grpc.CallOption) (Lease_LeaseKeepAliveClient, error)
+}
+
+type leaseClient struct {
+	cc *grpc.ClientConn
+}
+
+func NewLeaseClient(cc *grpc.ClientConn) LeaseClient {
+	return &leaseClient{cc}
+}
+
+func (c *leaseClient) LeaseCreate(ctx context.Context, in *LeaseCreateRequest, opts ...grpc.CallOption) (*LeaseCreateResponse, error) {
+	out := new(LeaseCreateResponse)
+	err := grpc.Invoke(ctx, "/etcdserverpb.Lease/LeaseCreate", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func (c *leaseClient) LeaseRevoke(ctx context.Context, in *LeaseRevokeRequest, opts ...grpc.CallOption) (*LeaseRevokeResponse, error) {
+	out := new(LeaseRevokeResponse)
+	err := grpc.Invoke(ctx, "/etcdserverpb.Lease/LeaseRevoke", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func (c *leaseClient) LeaseKeepAlive(ctx context.Context, opts ...grpc.CallOption) (Lease_LeaseKeepAliveClient, error) {
+	stream, err := grpc.NewClientStream(ctx, &_Lease_serviceDesc.Streams[0], c.cc, "/etcdserverpb.Lease/LeaseKeepAlive", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &leaseLeaseKeepAliveClient{stream}
+	return x, nil
+}
+
+type Lease_LeaseKeepAliveClient interface {
+	Send(*LeaseKeepAliveRequest) error
+	Recv() (*LeaseKeepAliveResponse, error)
+	grpc.ClientStream
+}
+
+type leaseLeaseKeepAliveClient struct {
+	grpc.ClientStream
+}
+
+func (x *leaseLeaseKeepAliveClient) Send(m *LeaseKeepAliveRequest) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *leaseLeaseKeepAliveClient) Recv() (*LeaseKeepAliveResponse, error) {
+	m := new(LeaseKeepAliveResponse)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// Server API for Lease service
+
+type LeaseServer interface {
+	// LeaseCreate creates a lease. A lease has a TTL. The lease will expire if the
+	// server does not receive a keepAlive within TTL from the lease holder.
+	// All keys attached to the lease will be expired and deleted if the lease expires.
+	// The key expiration generates an event in event history.
+	LeaseCreate(context.Context, *LeaseCreateRequest) (*LeaseCreateResponse, error)
+	// LeaseRevoke revokes a lease. All the key attached to the lease will be expired and deleted.
+	LeaseRevoke(context.Context, *LeaseRevokeRequest) (*LeaseRevokeResponse, error)
+	// KeepAlive keeps the lease alive.
+	LeaseKeepAlive(Lease_LeaseKeepAliveServer) error
+}
+
+func RegisterLeaseServer(s *grpc.Server, srv LeaseServer) {
+	s.RegisterService(&_Lease_serviceDesc, srv)
+}
+
+func _Lease_LeaseCreate_Handler(srv interface{}, ctx context.Context, codec grpc.Codec, buf []byte) (interface{}, error) {
+	in := new(LeaseCreateRequest)
+	if err := codec.Unmarshal(buf, in); err != nil {
+		return nil, err
+	}
+	out, err := srv.(LeaseServer).LeaseCreate(ctx, in)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func _Lease_LeaseRevoke_Handler(srv interface{}, ctx context.Context, codec grpc.Codec, buf []byte) (interface{}, error) {
+	in := new(LeaseRevokeRequest)
+	if err := codec.Unmarshal(buf, in); err != nil {
+		return nil, err
+	}
+	out, err := srv.(LeaseServer).LeaseRevoke(ctx, in)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func _Lease_LeaseKeepAlive_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(LeaseServer).LeaseKeepAlive(&leaseLeaseKeepAliveServer{stream})
+}
+
+type Lease_LeaseKeepAliveServer interface {
+	Send(*LeaseKeepAliveResponse) error
+	Recv() (*LeaseKeepAliveRequest, error)
+	grpc.ServerStream
+}
+
+type leaseLeaseKeepAliveServer struct {
+	grpc.ServerStream
+}
+
+func (x *leaseLeaseKeepAliveServer) Send(m *LeaseKeepAliveResponse) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *leaseLeaseKeepAliveServer) Recv() (*LeaseKeepAliveRequest, error) {
+	m := new(LeaseKeepAliveRequest)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+var _Lease_serviceDesc = grpc.ServiceDesc{
+	ServiceName: "etcdserverpb.Lease",
+	HandlerType: (*LeaseServer)(nil),
+	Methods: []grpc.MethodDesc{
+		{
+			MethodName: "LeaseCreate",
+			Handler:    _Lease_LeaseCreate_Handler,
+		},
+		{
+			MethodName: "LeaseRevoke",
+			Handler:    _Lease_LeaseRevoke_Handler,
+		},
+	},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "LeaseKeepAlive",
+			Handler:       _Lease_LeaseKeepAlive_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
+	},
+}
+
 func (m *ResponseHeader) Marshal() (data []byte, err error) {
 	size := m.Size()
 	data = make([]byte, size)
@@ -854,6 +1095,11 @@ func (m *PutRequest) MarshalTo(data []byte) (int, error) {
 			i += copy(data[i:], m.Value)
 		}
 	}
+	if m.Lease != 0 {
+		data[i] = 0x18
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Lease))
+	}
 	return i, nil
 }
 
@@ -1334,6 +1580,185 @@ func (m *WatchResponse) MarshalTo(data []byte) (int, error) {
 	return i, nil
 }
 
+func (m *LeaseCreateRequest) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseCreateRequest) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.Ttl != 0 {
+		data[i] = 0x8
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Ttl))
+	}
+	return i, nil
+}
+
+func (m *LeaseCreateResponse) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseCreateResponse) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.Header != nil {
+		data[i] = 0xa
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Header.Size()))
+		n14, err := m.Header.MarshalTo(data[i:])
+		if err != nil {
+			return 0, err
+		}
+		i += n14
+	}
+	if m.LeaseId != 0 {
+		data[i] = 0x10
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.LeaseId))
+	}
+	if m.Ttl != 0 {
+		data[i] = 0x18
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Ttl))
+	}
+	if len(m.Error) > 0 {
+		data[i] = 0x22
+		i++
+		i = encodeVarintRpc(data, i, uint64(len(m.Error)))
+		i += copy(data[i:], m.Error)
+	}
+	return i, nil
+}
+
+func (m *LeaseRevokeRequest) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseRevokeRequest) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.LeaseId != 0 {
+		data[i] = 0x8
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.LeaseId))
+	}
+	return i, nil
+}
+
+func (m *LeaseRevokeResponse) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseRevokeResponse) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.Header != nil {
+		data[i] = 0xa
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Header.Size()))
+		n15, err := m.Header.MarshalTo(data[i:])
+		if err != nil {
+			return 0, err
+		}
+		i += n15
+	}
+	return i, nil
+}
+
+func (m *LeaseKeepAliveRequest) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseKeepAliveRequest) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.LeaseId != 0 {
+		data[i] = 0x8
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.LeaseId))
+	}
+	return i, nil
+}
+
+func (m *LeaseKeepAliveResponse) Marshal() (data []byte, err error) {
+	size := m.Size()
+	data = make([]byte, size)
+	n, err := m.MarshalTo(data)
+	if err != nil {
+		return nil, err
+	}
+	return data[:n], nil
+}
+
+func (m *LeaseKeepAliveResponse) MarshalTo(data []byte) (int, error) {
+	var i int
+	_ = i
+	var l int
+	_ = l
+	if m.Header != nil {
+		data[i] = 0xa
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Header.Size()))
+		n16, err := m.Header.MarshalTo(data[i:])
+		if err != nil {
+			return 0, err
+		}
+		i += n16
+	}
+	if m.LeaseId != 0 {
+		data[i] = 0x10
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.LeaseId))
+	}
+	if m.Ttl != 0 {
+		data[i] = 0x18
+		i++
+		i = encodeVarintRpc(data, i, uint64(m.Ttl))
+	}
+	return i, nil
+}
+
 func encodeFixed64Rpc(data []byte, offset int, v uint64) int {
 	data[offset] = uint8(v)
 	data[offset+1] = uint8(v >> 8)
@@ -1437,6 +1862,9 @@ func (m *PutRequest) Size() (n int) {
 			n += 1 + l + sovRpc(uint64(l))
 		}
 	}
+	if m.Lease != 0 {
+		n += 1 + sovRpc(uint64(m.Lease))
+	}
 	return n
 }
 
@@ -1644,6 +2072,79 @@ func (m *WatchResponse) Size() (n int) {
 	return n
 }
 
+func (m *LeaseCreateRequest) Size() (n int) {
+	var l int
+	_ = l
+	if m.Ttl != 0 {
+		n += 1 + sovRpc(uint64(m.Ttl))
+	}
+	return n
+}
+
+func (m *LeaseCreateResponse) Size() (n int) {
+	var l int
+	_ = l
+	if m.Header != nil {
+		l = m.Header.Size()
+		n += 1 + l + sovRpc(uint64(l))
+	}
+	if m.LeaseId != 0 {
+		n += 1 + sovRpc(uint64(m.LeaseId))
+	}
+	if m.Ttl != 0 {
+		n += 1 + sovRpc(uint64(m.Ttl))
+	}
+	l = len(m.Error)
+	if l > 0 {
+		n += 1 + l + sovRpc(uint64(l))
+	}
+	return n
+}
+
+func (m *LeaseRevokeRequest) Size() (n int) {
+	var l int
+	_ = l
+	if m.LeaseId != 0 {
+		n += 1 + sovRpc(uint64(m.LeaseId))
+	}
+	return n
+}
+
+func (m *LeaseRevokeResponse) Size() (n int) {
+	var l int
+	_ = l
+	if m.Header != nil {
+		l = m.Header.Size()
+		n += 1 + l + sovRpc(uint64(l))
+	}
+	return n
+}
+
+func (m *LeaseKeepAliveRequest) Size() (n int) {
+	var l int
+	_ = l
+	if m.LeaseId != 0 {
+		n += 1 + sovRpc(uint64(m.LeaseId))
+	}
+	return n
+}
+
+func (m *LeaseKeepAliveResponse) Size() (n int) {
+	var l int
+	_ = l
+	if m.Header != nil {
+		l = m.Header.Size()
+		n += 1 + l + sovRpc(uint64(l))
+	}
+	if m.LeaseId != 0 {
+		n += 1 + sovRpc(uint64(m.LeaseId))
+	}
+	if m.Ttl != 0 {
+		n += 1 + sovRpc(uint64(m.Ttl))
+	}
+	return n
+}
+
 func sovRpc(x uint64) (n int) {
 	for {
 		n++
@@ -2082,6 +2583,22 @@ func (m *PutRequest) Unmarshal(data []byte) error {
 			}
 			m.Value = append([]byte{}, data[iNdEx:postIndex]...)
 			iNdEx = postIndex
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Lease", wireType)
+			}
+			m.Lease = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Lease |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
 		default:
 			var sizeOfWire int
 			for {
@@ -3399,6 +3916,504 @@ func (m *WatchResponse) Unmarshal(data []byte) error {
 
 	return nil
 }
+func (m *LeaseCreateRequest) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Ttl", wireType)
+			}
+			m.Ttl = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Ttl |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *LeaseCreateResponse) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Header", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				msglen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthRpc
+			}
+			postIndex := iNdEx + msglen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.Header == nil {
+				m.Header = &ResponseHeader{}
+			}
+			if err := m.Header.Unmarshal(data[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field LeaseId", wireType)
+			}
+			m.LeaseId = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.LeaseId |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Ttl", wireType)
+			}
+			m.Ttl = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Ttl |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 4:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Error", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				stringLen |= (uint64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthRpc
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Error = string(data[iNdEx:postIndex])
+			iNdEx = postIndex
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *LeaseRevokeRequest) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field LeaseId", wireType)
+			}
+			m.LeaseId = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.LeaseId |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *LeaseRevokeResponse) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Header", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				msglen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthRpc
+			}
+			postIndex := iNdEx + msglen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.Header == nil {
+				m.Header = &ResponseHeader{}
+			}
+			if err := m.Header.Unmarshal(data[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *LeaseKeepAliveRequest) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field LeaseId", wireType)
+			}
+			m.LeaseId = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.LeaseId |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
+func (m *LeaseKeepAliveResponse) Unmarshal(data []byte) error {
+	l := len(data)
+	iNdEx := 0
+	for iNdEx < l {
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := data[iNdEx]
+			iNdEx++
+			wire |= (uint64(b) & 0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Header", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				msglen |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthRpc
+			}
+			postIndex := iNdEx + msglen
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.Header == nil {
+				m.Header = &ResponseHeader{}
+			}
+			if err := m.Header.Unmarshal(data[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		case 2:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field LeaseId", wireType)
+			}
+			m.LeaseId = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.LeaseId |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Ttl", wireType)
+			}
+			m.Ttl = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Ttl |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			var sizeOfWire int
+			for {
+				sizeOfWire++
+				wire >>= 7
+				if wire == 0 {
+					break
+				}
+			}
+			iNdEx -= sizeOfWire
+			skippy, err := skipRpc(data[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthRpc
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	return nil
+}
 func skipRpc(data []byte) (n int, err error) {
 	l := len(data)
 	iNdEx := 0
diff --git a/etcdserver/etcdserverpb/rpc.proto b/etcdserver/etcdserverpb/rpc.proto
index e509a1318..c09eb547e 100644
--- a/etcdserver/etcdserverpb/rpc.proto
+++ b/etcdserver/etcdserverpb/rpc.proto
@@ -213,3 +213,34 @@ message WatchResponse {
   // TODO: support batched events response?
   storagepb.Event event = 2;
 }
+
+message LeaseCreateRequest {
+  // advisory ttl in seconds
+  int64 ttl = 1;
+}
+
+message LeaseCreateResponse {
+  ResponseHeader header = 1;
+  int64 lease_id = 2;
+  // server decided ttl in second
+  int64 ttl = 3;
+  string error = 4;
+}
+
+message LeaseRevokeRequest {
+  int64 lease_id = 1;
+}
+
+message LeaseRevokeResponse {
+  ResponseHeader header = 1;
+}
+
+message LeaseKeepAliveRequest {
+  int64 lease_id = 1;
+}
+
+message LeaseKeepAliveResponse {
+  ResponseHeader header = 1;
+  int64 lease_id = 2;
+  int64 ttl = 3;
+}
diff --git a/storage/storagepb/kv.pb.go b/storage/storagepb/kv.pb.go
index 0b6453ae3..bdcb565db 100644
--- a/storage/storagepb/kv.pb.go
+++ b/storage/storagepb/kv.pb.go
@@ -57,6 +57,9 @@ type KeyValue struct {
 	// increases its version.
 	Version int64  `protobuf:"varint,4,opt,name=version,proto3" json:"version,omitempty"`
 	Value   []byte `protobuf:"bytes,5,opt,name=value,proto3" json:"value,omitempty"`
+	// lease is the ID of the lease that attached to key.
+	// When the attached lease expires, the key will be deleted.
+	Lease int64 `protobuf:"varint,6,opt,name=lease,proto3" json:"lease,omitempty"`
 }
 
 func (m *KeyValue) Reset()         { *m = KeyValue{} }
@@ -126,6 +129,11 @@ func (m *KeyValue) MarshalTo(data []byte) (int, error) {
 			i += copy(data[i:], m.Value)
 		}
 	}
+	if m.Lease != 0 {
+		data[i] = 0x30
+		i++
+		i = encodeVarintKv(data, i, uint64(m.Lease))
+	}
 	return i, nil
 }
 
@@ -218,6 +226,9 @@ func (m *KeyValue) Size() (n int) {
 			n += 1 + l + sovKv(uint64(l))
 		}
 	}
+	if m.Lease != 0 {
+		n += 1 + sovKv(uint64(m.Lease))
+	}
 	return n
 }
 
@@ -367,6 +378,22 @@ func (m *KeyValue) Unmarshal(data []byte) error {
 			}
 			m.Value = append([]byte{}, data[iNdEx:postIndex]...)
 			iNdEx = postIndex
+		case 6:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Lease", wireType)
+			}
+			m.Lease = 0
+			for shift := uint(0); ; shift += 7 {
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := data[iNdEx]
+				iNdEx++
+				m.Lease |= (int64(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
 		default:
 			var sizeOfWire int
 			for {