diff --git a/include/Clock.h b/include/Clock.h
new file mode 100644
index 0000000..2ed163b
--- /dev/null
+++ b/include/Clock.h
@@ -0,0 +1,22 @@
+/*
+SPDX-License-Identifier: MIT
+Copyright (c) 2023 John Watts and the LuminaSensum contributors
+*/
+
+#ifndef CLOCK_H
+#define CLOCK_H
+
+#include "NetworkInterface.h"
+#include "sntp.h"
+#include <time.h>
+
+void clock_setup(void);
+
+struct timeval clock_time(void);
+
+SNTPError clock_sync(NetworkInterface &net);
+
+const char *clock_timestring(const char *format);
+const char *clock_iso8601string(void);
+
+#endif
diff --git a/src/Clock.cpp b/src/Clock.cpp
new file mode 100644
index 0000000..a8d6bf7
--- /dev/null
+++ b/src/Clock.cpp
@@ -0,0 +1,49 @@
+/*
+SPDX-License-Identifier: MIT
+Copyright (c) 2023 John Watts and the LuminaSensum contributors
+*/
+
+#include "Clock.h"
+
+void clock_setup(void) {
+	/* TODO: read RTC */
+	return;
+}
+
+struct timeval clock_time() {
+	/* TODO: read RTC */
+	struct timeval time = {0};
+	return time;
+}
+
+SNTPError clock_sync(NetworkInterface &net) {
+	struct timeval time;
+	SNTPError err;
+	err = sntp(net, "time.google.com", 123, &time);
+	if (err != SNTPSuccess) {
+		return err;
+	}
+	/* TODO: set RTC */
+	return SNTPSuccess;
+}
+
+const char *clock_timestring(const char *format) {
+	struct timeval time = clock_time();
+	struct tm *local_time = localtime(&time.tv_sec);
+
+	static char buffer[64];
+	size_t buffer_size = sizeof(buffer);
+	size_t buffer_written;
+	buffer_written = strftime(buffer, buffer_size, format, local_time);
+
+	if (buffer_written == 0) {
+		// It overflowed, so return something useful
+		return "(time overflow)";
+	} else {
+		return buffer;
+	}
+}
+
+const char *clock_iso8601string(void) {
+	return clock_timestring("%Y-%m-%dT%H:%M:%S");
+}