diff --git a/src/test/alert_tests.cpp b/src/test/alert_tests.cpp
new file mode 100644
index 00000000..c8d409db
--- /dev/null
+++ b/src/test/alert_tests.cpp
@@ -0,0 +1,132 @@
+//
+// Unit tests for alert system
+//
+
+#include <boost/foreach.hpp>
+#include <boost/test/unit_test.hpp>
+
+#include "alert.h"
+#include "serialize.h"
+#include "util.h"
+
+BOOST_AUTO_TEST_SUITE(Alert_tests)
+
+#if 0
+//
+// alertTests contains 7 alerts, generated with this code:
+// (SignAndSave code not shown, alert signing key is secret)
+//
+{
+    CAlert alert;
+    alert.nRelayUntil   = 60;
+    alert.nExpiration   = 24 * 60 * 60;
+    alert.nID           = 1;
+    alert.nCancel       = 0;   // cancels previous messages up to this ID number
+    alert.nMinVer       = 0;  // These versions are protocol versions
+    alert.nMaxVer       = 70001;
+    alert.nPriority     = 1;
+    alert.strComment    = "Alert comment";
+    alert.strStatusBar  = "Alert 1";
+
+    SignAndSave(alert, "test/alertTests");
+
+    alert.setSubVer.insert(std::string("/Satoshi:0.1.0/"));
+    alert.strStatusBar  = "Alert 1 for Satoshi 0.1.0";
+    SignAndSave(alert, "test/alertTests");
+
+    alert.setSubVer.insert(std::string("/Satoshi:0.2.0/"));
+    alert.strStatusBar  = "Alert 1 for Satoshi 0.1.0, 0.2.0";
+    SignAndSave(alert, "test/alertTests");
+
+    alert.setSubVer.clear();
+    alert.nID = 2;
+    alert.nCancel = 1;
+    alert.strStatusBar  = "Alert 2, cancels 1";
+    SignAndSave(alert, "test/alertTests");
+
+    alert.nExpiration += 60;
+    SignAndSave(alert, "test/alertTests");
+
+    alert.nMinVer = 11;
+    alert.nMaxVer = 22;
+    SignAndSave(alert, "test/alertTests");
+
+    alert.strStatusBar  = "Alert 2 for Satoshi 0.1.0";
+    alert.setSubVer.insert(std::string("/Satoshi:0.1.0/"));
+    SignAndSave(alert, "test/alertTests");
+}
+#endif
+
+
+std::vector<CAlert>
+read_alerts(const std::string& filename)
+{
+    std::vector<CAlert> result;
+
+    namespace fs = boost::filesystem;
+    fs::path testFile = fs::current_path() / "test" / "data" / filename;
+#ifdef TEST_DATA_DIR
+    if (!fs::exists(testFile))
+    {
+        testFile = fs::path(BOOST_PP_STRINGIZE(TEST_DATA_DIR)) / filename;
+    }
+#endif
+    FILE* fp = fopen(testFile.string().c_str(), "rb");
+    if (!fp) return result;
+
+
+    CAutoFile filein = CAutoFile(fp, SER_DISK, CLIENT_VERSION);
+    if (!filein) return result;
+
+    try {
+        while (!feof(filein))
+        {
+            CAlert alert;
+            filein >> alert;
+            result.push_back(alert);
+        }
+    }
+    catch (std::exception) { }
+
+    return result;
+}
+
+BOOST_AUTO_TEST_CASE(AlertApplies)
+{
+    SetMockTime(11);
+
+    std::vector<CAlert> alerts = read_alerts("alertTests");
+
+    BOOST_FOREACH(const CAlert& alert, alerts)
+    {
+        BOOST_CHECK(alert.CheckSignature());
+    }
+    // Matches:
+    BOOST_CHECK(alerts[0].AppliesTo(1, ""));
+    BOOST_CHECK(alerts[0].AppliesTo(70001, ""));
+    BOOST_CHECK(alerts[0].AppliesTo(1, "/Satoshi:11.11.11/"));
+
+    BOOST_CHECK(alerts[1].AppliesTo(1, "/Satoshi:0.1.0/"));
+    BOOST_CHECK(alerts[1].AppliesTo(70001, "/Satoshi:0.1.0/"));
+
+    BOOST_CHECK(alerts[2].AppliesTo(1, "/Satoshi:0.1.0/"));
+    BOOST_CHECK(alerts[2].AppliesTo(1, "/Satoshi:0.2.0/"));
+
+    // Don't match:
+    BOOST_CHECK(!alerts[0].AppliesTo(-1, ""));
+    BOOST_CHECK(!alerts[0].AppliesTo(70002, ""));
+
+    BOOST_CHECK(!alerts[1].AppliesTo(1, ""));
+    BOOST_CHECK(!alerts[1].AppliesTo(1, "Satoshi:0.1.0"));
+    BOOST_CHECK(!alerts[1].AppliesTo(1, "/Satoshi:0.1.0"));
+    BOOST_CHECK(!alerts[1].AppliesTo(1, "Satoshi:0.1.0/"));
+    BOOST_CHECK(!alerts[1].AppliesTo(-1, "/Satoshi:0.1.0/"));
+    BOOST_CHECK(!alerts[1].AppliesTo(70002, "/Satoshi:0.1.0/"));
+    BOOST_CHECK(!alerts[1].AppliesTo(1, "/Satoshi:0.2.0/"));
+
+    BOOST_CHECK(!alerts[2].AppliesTo(1, "/Satoshi:0.3.0/"));
+
+    SetMockTime(0);
+}
+
+BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/data/alertTests b/src/test/data/alertTests
new file mode 100644
index 00000000..126954e0
Binary files /dev/null and b/src/test/data/alertTests differ