diff --git a/test/unit/test_opencl_offloading.py b/test/unit/test_opencl_offloading.py
new file mode 100644
index 000000000..a2a84c01e
--- /dev/null
+++ b/test/unit/test_opencl_offloading.py
@@ -0,0 +1,73 @@
+import pytest
+pytest.importorskip("pyopencl")
+
+import sys
+import petsc4py
+petsc4py.init(sys.argv
+              + "-viennacl_backend opencl".split()
+              + "-viennacl_opencl_device_type cpu".split())
+from pyop2 import op2
+import pyopencl.array as cla
+import numpy as np
+
+
+def pytest_generate_tests(metafunc):
+    if "backend" in metafunc.fixturenames:
+        from pyop2.backends.opencl import opencl_backend
+        metafunc.parametrize("backend", [opencl_backend])
+
+
+def test_new_backend_raises_not_implemented_error():
+    from pyop2.backends import AbstractComputeBackend
+    unimplemented_backend = AbstractComputeBackend()
+
+    attrs = ["GlobalKernel", "Parloop", "Set", "ExtrudedSet", "MixedSet",
+             "Subset", "DataSet", "MixedDataSet", "Map", "MixedMap", "Dat",
+             "MixedDat", "DatView", "Mat", "Global", "GlobalDataSet",
+             "PETScVecType"]
+
+    for attr in attrs:
+        with pytest.raises(NotImplementedError):
+            getattr(unimplemented_backend, attr)
+
+
+def test_dat_with_petscvec_representation(backend):
+    op2.set_offloading_backend(backend)
+
+    nelems = 9
+    data = np.random.rand(nelems)
+    set_ = op2.compute_backend.Set(nelems)
+    dset = op2.compute_backend.DataSet(set_, 1)
+    dat = op2.compute_backend.Dat(dset, data.copy())
+
+    assert isinstance(dat.data_ro, np.ndarray)
+    dat.data[:] *= 3
+
+    with op2.offloading():
+        assert isinstance(dat.data_ro, cla.Array)
+        dat.data[:] *= 2
+
+    assert isinstance(dat.data_ro, np.ndarray)
+    np.testing.assert_allclose(dat.data_ro, 6*data)
+
+
+def test_dat_not_as_petscvec(backend):
+    op2.set_offloading_backend(backend)
+
+    nelems = 9
+    data = np.random.randint(low=-10, high=10,
+                             size=nelems,
+                             dtype=np.int64)
+    set_ = op2.compute_backend.Set(nelems)
+    dset = op2.compute_backend.DataSet(set_, 1)
+    dat = op2.compute_backend.Dat(dset, data.copy())
+
+    assert isinstance(dat.data_ro, np.ndarray)
+    dat.data[:] *= 3
+
+    with op2.offloading():
+        assert isinstance(dat.data_ro, cla.Array)
+        dat.data[:] *= 2
+
+    assert isinstance(dat.data_ro, np.ndarray)
+    np.testing.assert_allclose(dat.data_ro, 6*data)