diff --git a/presence/psensor.hpp b/presence/psensor.hpp
index 8ce2d7e..cc65fe0 100644
--- a/presence/psensor.hpp
+++ b/presence/psensor.hpp
@@ -1,5 +1,6 @@
 #pragma once
 #include <cstdint>
+#include <string>
 
 namespace phosphor
 {
@@ -78,6 +79,13 @@
 
     friend bool operator==(const PresenceSensor& l, const PresenceSensor& r);
 
+    /**
+     * @brief Called when this presence sensor doesn't agree with other ones.
+     *
+     * @param[in] fanInventoryPath - The fan inventory D-Bus object path.
+     */
+    virtual void logConflict(const std::string& fanInventoryPath) const = 0;
+
   private:
     /** @brief Unique sensor ID. */
     std::size_t id;