diff --git a/extensions/openpower-pels/registry.hpp b/extensions/openpower-pels/registry.hpp
new file mode 100644
index 0000000..e56bd42
--- /dev/null
+++ b/extensions/openpower-pels/registry.hpp
@@ -0,0 +1,179 @@
+#pragma once
+#include <filesystem>
+#include <nlohmann/json.hpp>
+#include <optional>
+#include <string>
+#include <vector>
+
+namespace openpower
+{
+namespace pels
+{
+namespace message
+{
+
+constexpr auto registryFileName = "message_registry.json";
+
+/**
+ * @brief Represents a message registry entry, which is used for creating a
+ *        PEL from an OpenBMC event log.
+ */
+struct Entry
+{
+    /**
+     * @brief The error name, like "xyz.openbmc_project.Error.Foo".
+     */
+    std::string name;
+
+    /**
+     * @brief The PEL subsystem field.
+     */
+    uint8_t subsystem;
+
+    /**
+     * @brief The optional PEL severity field.  If not specified, the PEL
+     *        will use the severity of the OpenBMC event log.
+     */
+    std::optional<uint8_t> severity;
+
+    /**
+     * @brief The optional severity field to use when in manufacturing tolerance
+     *        mode.
+     */
+    std::optional<uint8_t> mfgSeverity;
+
+    /**
+     * @brief The PEL action flags field.
+     */
+    uint16_t actionFlags;
+
+    /**
+     * @brief  The optional action flags to use instead when in manufacturing
+     * tolerance mode.
+     */
+    std::optional<uint16_t> mfgActionFlags;
+
+    /**
+     * @brief The PEL event type field.  If not specified, higher level code
+     *        will decide the value.
+     */
+    std::optional<uint8_t> eventType;
+
+    /**
+     * @brief The PEL event scope field.  If not specified, higher level code
+     *        will decide the value.
+     */
+    std::optional<uint8_t> eventScope;
+
+    // TODO: SRC related fields
+};
+
+/**
+ * @class Registry
+ *
+ * This class wraps the message registry JSON data and allows one to find
+ * the message registry entry pertaining to the error name.
+ *
+ * So that new registry files can easily be tested, the code will look for
+ * /etc/phosphor-logging/message_registry.json before looking for the real
+ * path.
+ */
+class Registry
+{
+  public:
+    Registry() = delete;
+    ~Registry() = default;
+    Registry(const Registry&) = default;
+    Registry& operator=(const Registry&) = default;
+    Registry(Registry&&) = default;
+    Registry& operator=(Registry&&) = default;
+
+    /**
+     * @brief Constructor
+     * @param[in] registryFile - The path to the file.
+     */
+    explicit Registry(const std::filesystem::path& registryFile) :
+        _registryFile(registryFile)
+    {
+    }
+
+    /**
+     * @brief Find a registry entry based on its error name.
+     *
+     * This function does do some basic sanity checking on the JSON contents,
+     * but there is also an external program that enforces a schema on the
+     * registry JSON that should catch all of these problems ahead of time.
+     *
+     * @param[in] name - The error name, like xyz.openbmc_project.Error.Foo
+     *
+     * @return optional<Entry> A filled in message registry structure if
+     *                         found, otherwise an empty optional object.
+     */
+    std::optional<Entry> lookup(const std::string& name);
+
+  private:
+    /**
+     * @brief The path to the registry JSON file.
+     */
+    std::filesystem::path _registryFile;
+};
+
+namespace helper
+{
+
+/**
+ * @brief A helper function to get the PEL subsystem value based on
+ *        the registry subsystem name.
+ *
+ * @param[in] subsystemName - The registry name for the subsystem
+ *
+ * @return uint8_t The PEL subsystem value
+ */
+uint8_t getSubsystem(const std::string& subsystemName);
+
+/**
+ * @brief A helper function to get the PEL severity value based on
+ *        the registry severity name.
+ *
+ * @param[in] severityName - The registry name for the severity
+ *
+ * @return uint8_t The PEL severity value
+ */
+uint8_t getSeverity(const std::string& severityName);
+
+/**
+ * @brief A helper function to get the action flags value based on
+ *        the action flag names used in the registry.
+ *
+ * @param[in] flags - The list of flag names from the registry.
+ *
+ * @return uint16_t - The bitfield of flags used in the PEL.
+ */
+uint16_t getActionFlags(const std::vector<std::string>& flags);
+
+/**
+ * @brief A helper function to get the PEL event type value based on
+ *        the registry event type name.
+ *
+ * @param[in] eventTypeName - The registry name for the event type
+ *
+ * @return uint8_t The PEL event type value
+ */
+uint8_t getEventType(const std::string& eventTypeName);
+
+/**
+ * @brief A helper function to get the PEL event scope value based on
+ *        the registry event scope name.
+ *
+ * @param[in] eventScopeName - The registry name for the event scope
+ *
+ * @return uint8_t The PEL event scope value
+ */
+uint8_t getEventScope(const std::string& eventScopeName);
+
+} // namespace helper
+
+} // namespace message
+
+} // namespace pels
+} // namespace openpower