diff --git a/deps/CMakeLists.txt b/deps/CMakeLists.txt
index ad5be2429..b13a88b45 100644
--- a/deps/CMakeLists.txt
+++ b/deps/CMakeLists.txt
@@ -51,6 +51,7 @@ FortranCInterface_HEADER(jlmpi_f2c.h MACRO_NAMESPACE "JLMPI_" SYMBOLS
   MPI_GET_PROCESSOR_NAME
   MPI_IALLGATHER
   MPI_IALLGATHERV
+  MPI_IALLREDUCE
   MPI_IALLTOALL
   MPI_IALLTOALLV
   MPI_IBARRIER
diff --git a/deps/gen_functions.c b/deps/gen_functions.c
index 91fb6188a..6cc4a67c8 100644
--- a/deps/gen_functions.c
+++ b/deps/gen_functions.c
@@ -39,6 +39,7 @@ int main(int argc, char *argv[]) {
          STRING(MPI_GET_PROCESSOR_NAME));
   printf("    :MPI_IALLGATHER         => \"%s\",\n", STRING(MPI_IALLGATHER));
   printf("    :MPI_IALLGATHERV        => \"%s\",\n", STRING(MPI_IALLGATHERV));
+  printf("    :MPI_IALLREDUCE         => \"%s\",\n", STRING(MPI_IALLREDUCE));
   printf("    :MPI_IALLTOALL          => \"%s\",\n", STRING(MPI_IALLTOALL));
   printf("    :MPI_IALLTOALLV         => \"%s\",\n", STRING(MPI_IALLTOALLV));
   printf("    :MPI_IBARRIER           => \"%s\",\n", STRING(MPI_IBARRIER));
diff --git a/src/mpi-base.jl b/src/mpi-base.jl
index dd9ab4bdf..7c2c2b251 100644
--- a/src/mpi-base.jl
+++ b/src/mpi-base.jl
@@ -571,6 +571,45 @@ function Ireduce{T}(object::T, op::Op, root::Integer, comm::Comm)
     req, isroot ? recvbuf[1] : nothing
 end
 
+function Allreduce{T}(sendbuf::MPIBuffertype{T}, count::Integer, op::Op, comm::Comm)
+    recvbuf = Array(T, count)
+    ccall(MPI_ALLREDUCE, Void,
+          (Ptr{T}, Ptr{T}, Ptr{Cint}, Ptr{Cint}, Ptr{Cint}, Ptr{Cint}, Ptr{Cint}),
+          sendbuf, recvbuf, &count, &mpitype(T), &op.val, &comm.val, &0)
+    recvbuf
+end
+
+function Allreduce{T}(sendbuf::Array{T}, op::Op, comm::Comm)
+    Allreduce(sendbuf, length(sendbuf), op, comm)
+end
+
+function Allreduce{T}(object::T, op::Op, comm::Comm)
+    sendbuf = T[object]
+    recvbuf = Allreduce(sendbuf, op, comm)
+    recvbuf[1]
+end
+
+function Iallreduce{T}(sendbuf::MPIBuffertype{T}, count::Integer, op::Op, comm::Comm)
+    rval = Ref{Cint}()
+    recvbuf = Array(T, count)
+    ccall(MPI_IALLREDUCE, Void,
+          (Ptr{T}, Ptr{T}, Ptr{Cint}, Ptr{Cint}, Ptr{Cint}, Ptr{Cint},
+           Ptr{Cint}, Ptr{Cint}),
+          sendbuf, recvbuf, &count, &mpitype(T), &op.val, &comm.val,
+          rval, &0)
+    Request(rval[], sendbuf), recvbuf
+end
+
+function Iallreduce{T}(sendbuf::Array{T}, op::Op, comm::Comm)
+    Iallreduce(sendbuf, length(sendbuf), op, comm)
+end
+
+function Iallreduce{T}(object::T, op::Op, comm::Comm)
+    sendbuf = T[object]
+    req, recvbuf = Iallreduce(sendbuf, op, comm)
+    req, recvbuf[1]
+end
+
 function Scatter{T}(sendbuf::MPIBuffertype{T},
                     count::Integer, root::Integer, comm::Comm)
     recvbuf = Array(T, count)
diff --git a/src/win_mpiconstants.jl b/src/win_mpiconstants.jl
index c58a6f7e7..f1a59deaf 100644
--- a/src/win_mpiconstants.jl
+++ b/src/win_mpiconstants.jl
@@ -65,6 +65,8 @@ const MPI_ALLGATHER = (:MPI_ALLGATHER, "msmpi.dll")
 const MPI_ALLGATHERV = (:MPI_ALLGATHERV, "msmpi.dll")
 const MPI_IALLGATHER = (:MPI_ALLGATHER, "msmpi.dll")
 const MPI_IALLGATHERV = (:MPI_ALLGATHERV, "msmpi.dll")
+const MPI_ALLREDUCE = (:MPI_ALLREDUCE, "msmpi.dll")
+const MPI_IALLREDUCE = (:MPI_IALLREDUCE, "msmpi.dll")
 const MPI_ALLTOALL = (:MPI_ALLTOALL, "msmpi.dll")
 const MPI_ALLTOALLV = (:MPI_ALLTOALLV, "msmpi.dll")
 const MPI_IALLTOALL = (:MPI_IALLTOALL, "msmpi.dll")
diff --git a/test/test_allreduce.jl b/test/test_allreduce.jl
new file mode 100644
index 000000000..5d808f682
--- /dev/null
+++ b/test/test_allreduce.jl
@@ -0,0 +1,30 @@
+using Base.Test
+
+using MPI
+
+MPI.Init()
+
+comm = MPI.COMM_WORLD
+size = MPI.Comm_size(comm)
+rank = MPI.Comm_rank(comm)
+
+val = sum(0:size-1)
+@test MPI.Allreduce(rank, MPI.SUM, comm) == val
+
+val = size-1
+@test MPI.Allreduce(rank, MPI.MAX, comm) == val
+
+val = 0
+@test MPI.Allreduce(rank, MPI.MIN, comm) == val
+
+mesg = collect(1.0:5.0)
+sum_mesg = MPI.Allreduce(mesg, MPI.SUM, comm)
+@test isapprox(norm(sum_mesg-size*mesg), 0.0)
+
+mesg = collect(1.0:5.0)
+req, sum_mesg = MPI.Iallreduce(mesg, MPI.SUM, comm)
+MPI.Wait!(req)
+sum_mesg = sum_mesg
+@test isapprox(norm(sum_mesg-size*mesg), 0.0)
+
+MPI.Finalize()