diff --git a/Project.toml b/Project.toml
index 6dfcf67..35ba2d9 100644
--- a/Project.toml
+++ b/Project.toml
@@ -9,3 +9,9 @@ Libdl = "8f399da3-3557-5675-b5ff-fb832c97cbdb"
 MPI = "da04e1cc-30fd-572f-bb4f-1f8673147195"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 SparseMatricesCSR = "a0a7dd2c-ebf4-11e9-1f05-cf50bc540ca1"
+
+[extras]
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[targets]
+test = ["Test"]
diff --git a/src/HYPRE.jl b/src/HYPRE.jl
index abc7741..33544f3 100644
--- a/src/HYPRE.jl
+++ b/src/HYPRE.jl
@@ -66,6 +66,8 @@ using SparseMatricesCSR: SparseMatrixCSR, colvals
 using MPI: MPI
 using .LibHYPRE
 
+export HYPREMatrix, HYPREVector
+
 module Internals
     function check_n_rows end
     function to_hypre_data end
diff --git a/test/runtests.jl b/test/runtests.jl
new file mode 100644
index 0000000..7a06424
--- /dev/null
+++ b/test/runtests.jl
@@ -0,0 +1,78 @@
+using HYPRE
+using HYPRE.LibHYPRE
+using Test
+using SparseArrays
+using SparseMatricesCSR
+
+using MPI
+MPI.Init()
+
+@testset "HYPREMatrix" begin
+    H = HYPREMatrix()
+    @test H.IJMatrix == HYPRE_IJMatrix(C_NULL)
+    @test H.ParCSRMatrix == HYPRE_ParCSRMatrix(C_NULL)
+
+    ilower, iupper = 4, 6
+    CSC = convert(SparseMatrixCSC{HYPRE_Complex, HYPRE_Int}, sparse([
+        1 2 0 0 3
+        0 4 0 5 0
+        0 6 7 0 8
+    ]))
+    CSR = sparsecsr(findnz(CSC)..., size(CSC)...)
+    @test CSC == CSR
+    csc = HYPRE.Internals.to_hypre_data(CSC, ilower, iupper)
+    csr = HYPRE.Internals.to_hypre_data(CSR, ilower, iupper)
+    @test csc[1]::HYPRE_Int == csr[1]::HYPRE_Int == 3 # nrows
+    @test csc[2]::Vector{HYPRE_Int} == csr[2]::Vector{HYPRE_Int} == [3, 2, 3] # ncols
+    @test csc[3]::Vector{HYPRE_BigInt} == csr[3]::Vector{HYPRE_BigInt} == [4, 5, 6] # rows
+    @test csc[4]::Vector{HYPRE_BigInt} == csr[4]::Vector{HYPRE_BigInt} == [1, 2, 5, 2, 4, 2, 3, 5] # cols
+    @test csc[5]::Vector{HYPRE_Complex} == csr[5]::Vector{HYPRE_Complex} == 1:8 # values
+
+    # Optimizations for CSR matrix
+    @test csr[4] == CSR.colval
+    @test_broken csr[4] === CSR.colval
+    @test csr[5] == CSR.nzval
+    @test_broken csr[5]::Vector{HYPRE_Complex} === CSR.nzval
+
+    @test_throws ArgumentError HYPRE.Internals.to_hypre_data(CSC, ilower, iupper-1)
+    @test_throws ArgumentError HYPRE.Internals.to_hypre_data(CSR, ilower, iupper+1)
+
+    # Converting SparseMatrixCS(C|R) to HYPREMatrix
+    ilower, iupper = 6, 10
+    CSC = sprand(5, 10, 0.3)
+    CSR = sparsecsr(findnz(CSC)..., size(CSC)...)
+    @test CSC == CSR
+    H = HYPREMatrix(CSC, ilower,  iupper)
+    @test H.IJMatrix != HYPRE_IJMatrix(C_NULL)
+    @test H.ParCSRMatrix != HYPRE_ParCSRMatrix(C_NULL)
+    H = HYPREMatrix(CSR, ilower,  iupper)
+    @test H.IJMatrix != HYPRE_IJMatrix(C_NULL)
+    @test H.ParCSRMatrix != HYPRE_ParCSRMatrix(C_NULL)
+end
+
+@testset "HYPREVector" begin
+    h = HYPREVector()
+    @test h.IJVector == HYPRE_IJVector(C_NULL)
+    @test h.ParVector == HYPRE_ParVector(C_NULL)
+
+    ilower, iupper = 1, 10
+    b = rand(HYPRE_Complex, 10)
+    nvalues, indices, values = HYPRE.Internals.to_hypre_data(b, ilower, iupper)
+    @test nvalues::HYPRE_Int == 10
+    @test indices::Vector{HYPRE_Int} == collect(1:10)
+    @test values::Vector{HYPRE_Complex} === b # === for correct eltype
+
+    b = rand(1:10, 10)
+    nvalues, indices, values = HYPRE.Internals.to_hypre_data(b, ilower, iupper)
+    @test nvalues::HYPRE_Int == 10
+    @test indices::Vector{HYPRE_Int} == collect(1:10)
+    @test values::Vector{HYPRE_Complex} == b # == for other eltype
+    @test_throws ArgumentError HYPRE.Internals.to_hypre_data([1, 2], ilower, iupper)
+
+    # Converting Vector to HYPREVector
+    b = rand(HYPRE_Complex, 10)
+    h = HYPREVector(b, ilower, iupper)
+    @test h.IJVector != HYPRE_IJVector(C_NULL)
+    @test h.ParVector != HYPRE_ParVector(C_NULL)
+    @test_throws ArgumentError HYPREVector([1, 2], ilower, iupper)
+end