diff --git a/attn/attn_monitor.cpp b/attn/attn_monitor.cpp
new file mode 100644
index 0000000..2db8af1
--- /dev/null
+++ b/attn/attn_monitor.cpp
@@ -0,0 +1,102 @@
+#include "attn_monitor.hpp"
+
+#include "attn_handler.hpp"
+
+#include <phosphor-logging/log.hpp>
+
+using namespace phosphor::logging;
+
+namespace attn
+{
+
+/** @brief Register a callback for gpio event */
+void AttnMonitor::scheduleGPIOEvent()
+{
+    std::string logMessage = "[ATTN] ... waiting for events ...";
+    log<level::INFO>(logMessage.c_str());
+
+    // Register async callback, note that callback is a
+    // lambda function with "this" pointer captured
+    iv_gpioEventDescriptor.async_wait(
+        boost::asio::posix::stream_descriptor::wait_read,
+        [this](const boost::system::error_code& ec) {
+            if (ec)
+            {
+                std::string logMessage = "[ATTN] ATTN GPIO Async error: " +
+                                         std::string(ec.message());
+                log<level::INFO>(logMessage.c_str());
+            }
+            else
+            {
+                handleGPIOEvent(); // gpio trigger detected
+            }
+            return;
+        }); // register async callback
+}
+
+/** @brief Handle the GPIO state change event */
+void AttnMonitor::handleGPIOEvent()
+{
+    gpiod_line_event gpioEvent;
+    std::string logMessage;
+
+    if (gpiod_line_event_read_fd(iv_gpioEventDescriptor.native_handle(),
+                                 &gpioEvent) < 0)
+    {
+        logMessage = "[ATTN] ATTN GPIO Failed can't read file descriptor!";
+        log<level::INFO>(logMessage.c_str());
+    }
+    else
+    {
+        switch (gpiod_line_get_value(iv_gpioLine))
+        {
+            // active attention when gpio == 0
+            case 0:
+                attnHandler();
+                break;
+
+            // gpio == 1, GPIO handler should not be executing
+            case 1:
+                logMessage = "[ATTN] ATTN GPIO sync!";
+                log<level::INFO>(logMessage.c_str());
+                break;
+
+            // unexpected value
+            default:
+                logMessage = "[ATTN] ATTN GPIO read unexpected valuel!";
+                log<level::INFO>(logMessage.c_str());
+        }
+    }
+    scheduleGPIOEvent(); // continue monitoring gpio
+}
+
+/** @brief Request a GPIO line for monitoring attention events */
+void AttnMonitor::requestGPIOEvent()
+{
+    if (0 != gpiod_line_request(iv_gpioLine, &iv_gpioConfig, 0))
+    {
+        std::string logMessage = "[ATTN] failed request for GPIO";
+        log<level::INFO>(logMessage.c_str());
+    }
+    else
+    {
+        int gpioLineFd;
+
+        gpioLineFd = gpiod_line_event_get_fd(iv_gpioLine);
+        if (gpioLineFd < 0)
+        {
+            std::string logMessage = "[ATTN] failed to get file descriptor";
+            log<level::INFO>(logMessage.c_str());
+        }
+        else
+        {
+            // Register file descriptor for monitoring
+            iv_gpioEventDescriptor.assign(gpioLineFd);
+
+            // Start monitoring
+            scheduleGPIOEvent();
+        }
+    }
+}
+
+} // namespace attn