diff --git a/htmlSanityCheck-core/src/test/groovy/org/aim42/htmlsanitycheck/report/HtmlReporterTest.groovy b/htmlSanityCheck-core/src/test/groovy/org/aim42/htmlsanitycheck/report/HtmlReporterTest.groovy
new file mode 100644
index 00000000..7fca33cb
--- /dev/null
+++ b/htmlSanityCheck-core/src/test/groovy/org/aim42/htmlsanitycheck/report/HtmlReporterTest.groovy
@@ -0,0 +1,68 @@
+package org.aim42.htmlsanitycheck.report
+
+import org.aim42.htmlsanitycheck.collect.PerRunResults
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.TemporaryFolder
+
+import java.nio.file.Files
+
+import static org.junit.Assert.assertTrue
+import static org.junit.Assert.fail
+
+class HtmlReporterTest {
+
+    private HtmlReporter htmlReporter
+    private PerRunResults runResults
+
+    @Rule
+    public TemporaryFolder tempDir = new TemporaryFolder()
+
+    @Before
+    void setUp() {
+        runResults = new PerRunResults()
+        htmlReporter = new HtmlReporter(runResults, tempDir.getRoot().getAbsolutePath())
+    }
+
+    @Test
+    void testInitReport() {
+        htmlReporter.initReport()
+        File reportFile = new File(tempDir.getRoot(), "index.html")
+        assertTrue("Report file should be created", reportFile.exists())
+    }
+
+    @Test
+    void testWrite() {
+        htmlReporter.initReport()
+        htmlReporter.write("Test content")
+        htmlReporter.closeReport()
+        File reportFile = new File(tempDir.getRoot(), "index.html")
+        try {
+            String content = new String(Files.readAllBytes(reportFile.toPath()))
+            assertTrue("Report file should contain written content", content.contains("Test content"))
+        } catch (IOException e) {
+            fail("Failed to read report file: ${e}")
+        }
+    }
+
+    // Add more test methods for other methods in HtmlReporter
+}
+
+/*======================================================================
+
+Copyright Gernot Starke and aim42 contributors
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an
+ "AS IS" BASIS,WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ ======================================================================*/