diff --git a/test_ffprobe_command.py b/test_ffprobe_command.py
new file mode 100644
index 0000000..1cd6e07
--- /dev/null
+++ b/test_ffprobe_command.py
@@ -0,0 +1,110 @@
+import shutil
+from pathlib import Path
+import tempfile
+import unittest
+
+from shell_command import (
+    ShellCommand, FFprobeCommand
+)
+
+
+class TestFFprobeCommand(unittest.TestCase):
+    """Test the FFprobeCommand class.
+    """
+
+    def setUp(self):
+        """Initialisation. Make sure the input and output options are
+        explicitly set otherwise they hang around from previous tests.
+        A fresh temporary file is created for each test.
+        """
+        self.tmpfile = tempfile.NamedTemporaryFile()
+        self.command = FFprobeCommand(
+            input_options=["foo", self.tmpfile.name], output_options=["bar"])
+        self.expected_executable = shutil.which("ffprobe")
+        self.expected_base_options = [
+            "-loglevel", "error",
+            "-show_entries", "format:stream",
+            "-print_format", "json",
+        ]
+        self.expected_input_options = ["foo", self.tmpfile.name]
+        self.expected_output_options = ["bar"]
+
+    def tearDown(self):
+        """Cleanup.
+        """
+        self.tmpfile.close()
+        self.command = None
+    
+    def test_base_options(self):
+        """Test that base options match expected.
+        """
+        self.assertEqual(
+            self.command._base_options, self.expected_base_options)
+    
+    def test_input_options(self):
+        """Test that input options match expected.
+        """
+        self.assertEqual(
+            self.command.input_options, self.expected_input_options)
+    
+    def test_output_options(self):
+        """Test that output options match expected.
+        """
+        self.assertEqual(
+            self.command.output_options, self.expected_output_options)
+    
+    def test_executable_string(self):
+        """Test that executable path matches expected.
+        """
+        self.assertEqual(self.command.executable_string(quote=False),
+            self.expected_executable)
+        # Note: don't explicitly specify quoted value, because
+        # the executable path will vary across different systems.
+        self.assertEqual(self.command.executable_string(quote=True),
+            ShellCommand.shellquote(self.expected_executable))
+
+    def test_argument_string(self):
+        """Test that the argument string matches expected.
+        """
+        self.maxDiff = None
+        args = (self.expected_base_options + self.expected_input_options +
+            self.expected_output_options)
+        self.assertEqual(self.command.argument_string(quote=False),
+            " ".join(args))
+        self.assertEqual(self.command.argument_string(quote=True),
+            " ".join([ShellCommand.shellquote(a) for a in args]))
+
+    def test_argument_list(self):
+        """Test that the argument list matches expected.
+        """
+        self.assertEqual(self.command.argument_list(),
+            self.expected_base_options + self.expected_input_options +
+            self.expected_output_options)
+
+    def test_command_string(self):
+        """Test that the command string matches expected.
+        """
+        args = (self.expected_base_options + self.expected_input_options +
+            self.expected_output_options)
+        expected_cmd_unquoted = (
+            "{exe} {arg}".format(exe=self.expected_executable,
+                arg=" ".join(args))
+        )
+        expected_cmd_quoted = (
+            '{exe} {arg}'.format(
+                exe=ShellCommand.shellquote(self.expected_executable),
+                arg=" ".join([ShellCommand.shellquote(a) for a in args]))
+        )
+        self.assertEqual(self.command.command_string(quote=False),
+            expected_cmd_unquoted)
+        self.assertEqual(self.command.command_string(quote=True),
+            expected_cmd_quoted)
+    
+    def test_last_modified(self):
+        """Test that last modified time matches tmpfile on disk.
+        """
+        self.assertEqual(
+            self.command.last_modified,
+            Path(self.tmpfile.name).stat().st_mtime)
+
+    # get_entries()?