diff --git a/src/HYPRE.jl b/src/HYPRE.jl
index cf7d66f..b8ab947 100644
--- a/src/HYPRE.jl
+++ b/src/HYPRE.jl
@@ -24,21 +24,19 @@ include("Internals.jl")
 ###############################
 
 mutable struct HYPREMatrix # <: AbstractMatrix{HYPRE_Complex}
+    #= const =# comm::MPI.Comm
+    #= const =# ilower::HYPRE_BigInt
+    #= const =# iupper::HYPRE_BigInt
+    #= const =# jlower::HYPRE_BigInt
+    #= const =# jupper::HYPRE_BigInt
     IJMatrix::HYPRE_IJMatrix
     ParCSRMatrix::HYPRE_ParCSRMatrix
-    HYPREMatrix() = new(C_NULL, C_NULL)
 end
 
-mutable struct HYPREVector # <: AbstractVector{HYPRE_Complex}
-    IJVector::HYPRE_IJVector
-    ParVector::HYPRE_ParVector
-    HYPREVector() = new(C_NULL, C_NULL)
-end
-
-# Create a new IJMatrix, set the object type, prepare for setting values
-function Internals.init_matrix(comm::MPI.Comm, ilower, iupper)
+function HYPREMatrix(comm::MPI.Comm, ilower::Integer,        iupper::Integer,
+                                     jlower::Integer=ilower, jupper::Integer=iupper)
     # Create the IJ matrix
-    A = HYPREMatrix()
+    A = HYPREMatrix(comm, ilower, iupper, jlower, jupper, C_NULL, C_NULL)
     IJMatrixRef = Ref{HYPRE_IJMatrix}(C_NULL)
     @check HYPRE_IJMatrixCreate(comm, ilower, iupper, ilower, iupper, IJMatrixRef)
     A.IJMatrix = IJMatrixRef[]
@@ -51,21 +49,17 @@ function Internals.init_matrix(comm::MPI.Comm, ilower, iupper)
     return A
 end
 
-# Finalize the matrix and fetch the assembled matrix
-# This should be called after setting all the values
-function Internals.assemble_matrix(A::HYPREMatrix)
-    # Finalize after setting all values
-    @check HYPRE_IJMatrixAssemble(A.IJMatrix)
-    # Fetch the assembled CSR matrix
-    ParCSRMatrixRef = Ref{Ptr{Cvoid}}(C_NULL)
-    @check HYPRE_IJMatrixGetObject(A.IJMatrix, ParCSRMatrixRef)
-    A.ParCSRMatrix = convert(Ptr{HYPRE_ParCSRMatrix}, ParCSRMatrixRef[])
-    return A
+mutable struct HYPREVector # <: AbstractVector{HYPRE_Complex}
+    #= const =# comm::MPI.Comm
+    #= const =# ilower::HYPRE_BigInt
+    #= const =# iupper::HYPRE_BigInt
+    IJVector::HYPRE_IJVector
+    ParVector::HYPRE_ParVector
 end
 
-function Internals.init_vector(comm::MPI.Comm, ilower, iupper)
+function HYPREVector(comm::MPI.Comm, ilower::Integer, iupper::Integer)
     # Create the IJ vector
-    b = HYPREVector()
+    b = HYPREVector(comm, ilower, iupper, C_NULL, C_NULL)
     b_ref = Ref{HYPRE_IJVector}(C_NULL)
     @check HYPRE_IJVectorCreate(comm, ilower, iupper, b_ref)
     b.IJVector = b_ref[]
@@ -78,6 +72,18 @@ function Internals.init_vector(comm::MPI.Comm, ilower, iupper)
     return b
 end
 
+# Finalize the matrix and fetch the assembled matrix
+# This should be called after setting all the values
+function Internals.assemble_matrix(A::HYPREMatrix)
+    # Finalize after setting all values
+    @check HYPRE_IJMatrixAssemble(A.IJMatrix)
+    # Fetch the assembled CSR matrix
+    ParCSRMatrixRef = Ref{Ptr{Cvoid}}(C_NULL)
+    @check HYPRE_IJMatrixGetObject(A.IJMatrix, ParCSRMatrixRef)
+    A.ParCSRMatrix = convert(Ptr{HYPRE_ParCSRMatrix}, ParCSRMatrixRef[])
+    return A
+end
+
 function Internals.assemble_vector(b::HYPREVector)
     # Finalize after setting all values
     @check HYPRE_IJVectorAssemble(b.IJVector)
@@ -89,27 +95,29 @@ function Internals.assemble_vector(b::HYPREVector)
 end
 
 function Internals.get_proc_rows(b::HYPREVector)
-    jlower_ref = Ref{HYPRE_BigInt}()
-    jupper_ref = Ref{HYPRE_BigInt}()
-    @check HYPRE_IJVectorGetLocalRange(b.IJVector, jlower_ref, jupper_ref)
-    jlower = jlower_ref[]
-    jupper = jupper_ref[]
-    return jlower, jupper
+    # ilower_ref = Ref{HYPRE_BigInt}()
+    # iupper_ref = Ref{HYPRE_BigInt}()
+    # @check HYPRE_IJVectorGetLocalRange(b.IJVector, ilower_ref, iupper_ref)
+    # ilower = ilower_ref[]
+    # iupper = iupper_ref[]
+    # return ilower, iupper
+    return b.ilower, b.iupper
 end
 
 function Internals.get_comm(b::HYPREVector)
-    # The MPI communicator is (currently) the first field of the struct:
-    # https://github.com/hypre-space/hypre/blob/48de53e675af0e23baf61caa73d89fd9f478f453/src/IJ_mv/IJ_vector.h#L23
-    # Fingers crossed this doesn't change!
-    @assert b.IJVector != C_NULL
-    comm = unsafe_load(Ptr{MPI.Comm}(b.IJVector))
-    return comm
+    # # The MPI communicator is (currently) the first field of the struct:
+    # # https://github.com/hypre-space/hypre/blob/48de53e675af0e23baf61caa73d89fd9f478f453/src/IJ_mv/IJ_vector.h#L23
+    # # Fingers crossed this doesn't change!
+    # @assert b.IJVector != C_NULL
+    # comm = unsafe_load(Ptr{MPI.Comm}(b.IJVector))
+    # return comm
+    return b.comm
 end
 
 function Base.zero(b::HYPREVector)
     jlower, jupper = Internals.get_proc_rows(b)
     comm = Internals.get_comm(b)
-    x = Internals.init_vector(comm, jlower, jupper)
+    x = HYPREVector(comm, jlower, jupper)
     # TODO All values 0 by default? Looks like it... Work in progress patch to hypre to
     #      support IJVectorSetConstantValues analoguous to IJMatrixSetConstantValues.
     nvalues = jupper - jlower + 1
@@ -201,7 +209,7 @@ end
 
 # TODO: Default to ilower = 1, iupper = size(B, 1)?
 function HYPREMatrix(B::Union{SparseMatrixCSC,SparseMatrixCSR}, ilower, iupper, comm::MPI.Comm=MPI.COMM_WORLD)
-    A = Internals.init_matrix(comm, ilower, iupper)
+    A = HYPREMatrix(comm, ilower, iupper)
     nrows, ncols, rows, cols, values = Internals.to_hypre_data(B, ilower, iupper)
     @check HYPRE_IJMatrixSetValues(A.IJMatrix, nrows, ncols, rows, cols, values)
     Internals.assemble_matrix(A)
@@ -222,7 +230,7 @@ end
 
 # TODO: Default to ilower = 1, iupper = length(x)?
 function HYPREVector(x::Vector, ilower, iupper, comm=MPI.COMM_WORLD)
-    b = Internals.init_vector(comm, ilower, iupper)
+    b = HYPREVector(comm, ilower, iupper)
     nvalues, indices, values = Internals.to_hypre_data(x, ilower, iupper)
     @check HYPRE_IJVectorSetValues(b.IJVector, nvalues, indices, values)
     Internals.assemble_vector(b)
@@ -360,7 +368,7 @@ function HYPREMatrix(B::PSparseMatrix)
     # Fetch rows owned by this process
     ilower, iupper = Internals.get_proc_rows(B)
     # Create the IJ matrix
-    A = Internals.init_matrix(comm, ilower, iupper)
+    A = HYPREMatrix(comm, ilower, iupper)
     # Set all the values
     map_parts(B.values, B.rows.partition, B.cols.partition) do Bv, Br, Bc
         nrows, ncols, rows, cols, values = Internals.to_hypre_data(Bv, Br, Bc)
@@ -382,7 +390,7 @@ function HYPREVector(v::PVector)
     # Fetch rows owned by this process
     ilower, iupper = Internals.get_proc_rows(v)
     # Create the IJ vector
-    b = Internals.init_vector(comm, ilower, iupper)
+    b = HYPREVector(comm, ilower, iupper)
     # Set all the values
     map_parts(v.values, v.owned_values, v.rows.partition) do _, vo, vr
         ilower_part = vr.lid_to_gid[vr.oid_to_lid.start]
diff --git a/src/Internals.jl b/src/Internals.jl
index ec43ace..208e8e3 100644
--- a/src/Internals.jl
+++ b/src/Internals.jl
@@ -6,8 +6,6 @@ function check_n_rows end
 function to_hypre_data end
 function get_comm end
 function get_proc_rows end
-function init_matrix end
-function init_vector end
 function assemble_matrix end
 function assemble_vector end
 function set_options end
diff --git a/test/runtests.jl b/test/runtests.jl
index ab5c95c..25479e2 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -14,11 +14,7 @@ MPI.Init()
 HYPRE_Init()
 
 @testset "HYPREMatrix" begin
-    H = HYPREMatrix()
-    @test H.IJMatrix == HYPRE_IJMatrix(C_NULL)
-    @test H.ParCSRMatrix == HYPRE_ParCSRMatrix(C_NULL)
-
-    H = Internals.init_matrix(MPI.COMM_WORLD, 1, 5)
+    H = HYPREMatrix(MPI.COMM_WORLD, 1, 5)
     @test H.IJMatrix != HYPRE_IJMatrix(C_NULL)
     @test H.ParCSRMatrix == HYPRE_ParCSRMatrix(C_NULL)
     Internals.assemble_matrix(H)
@@ -164,11 +160,7 @@ end
 end
 
 @testset "HYPREVector" begin
-    h = HYPREVector()
-    @test h.IJVector == HYPRE_IJVector(C_NULL)
-    @test h.ParVector == HYPRE_ParVector(C_NULL)
-
-    h = Internals.init_vector(MPI.COMM_WORLD, 1, 5)
+    h = HYPREVector(MPI.COMM_WORLD, 1, 5)
     @test h.IJVector != HYPRE_IJVector(C_NULL)
     @test h.ParVector == HYPRE_ParVector(C_NULL)
     Internals.assemble_vector(h)