diff --git a/tests/test_util.py b/tests/test_util.py
new file mode 100644
index 0000000..81411e6
--- /dev/null
+++ b/tests/test_util.py
@@ -0,0 +1,14 @@
+import numpy as np
+from pysb.pkpd.pk_models import twocomp
+from pysb.pkpd import simulate
+
+
+def test_simulate():
+    tspan = np.arange(10)
+    sim_traj = simulate(twocomp, tspan)
+    assert len(sim_traj) == 10
+    assert len(sim_traj[0]) == 2
+
+
+if __name__ == "__main__":
+    test_simulate()