diff --git a/power-supply/argument.cpp b/power-supply/argument.cpp
deleted file mode 100644
index 7b671d8..0000000
--- a/power-supply/argument.cpp
+++ /dev/null
@@ -1,102 +0,0 @@
-/**
- * Copyright © 2017 IBM Corporation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include "argument.hpp"
-
-#include <algorithm>
-#include <cassert>
-#include <iostream>
-#include <iterator>
-
-namespace phosphor
-{
-namespace power
-{
-
-ArgumentParser::ArgumentParser(int argc, char** argv)
-{
-    auto option = 0;
-    while (-1 != (option = getopt_long(argc, argv, optionStr, options, NULL)))
-    {
-        if ((option == '?') || (option == 'h'))
-        {
-            usage(argv);
-            exit(-1);
-        }
-
-        auto i = &options[0];
-        while ((i->val != option) && (i->val != 0))
-        {
-            ++i;
-        }
-
-        if (i->val)
-        {
-            arguments[i->name] = (i->has_arg ? optarg : trueString);
-        }
-    }
-}
-
-const std::string& ArgumentParser::operator[](const std::string& opt)
-{
-    auto i = arguments.find(opt);
-    if (i == arguments.end())
-    {
-        return emptyString;
-    }
-    else
-    {
-        return i->second;
-    }
-}
-
-void ArgumentParser::usage(char** argv)
-{
-    std::cerr << "Usage: " << argv[0] << " [options]\n";
-    std::cerr << "Options:\n";
-    std::cerr << "    --help                              Print this menu\n";
-    std::cerr << "    --path=<objpath>                    Path to location to"
-                 " monitor\n";
-    std::cerr << "    --instance=<instance number>        Instance number for"
-                 " this power supply\n";
-    std::cerr << "    --inventory=<inventory path>        Inventory path for"
-                 " this power supply\n";
-    std::cerr << "    --num-history-records=<num records> Number of input"
-                 " power history records to provide on D-Bus\n";
-    std::cerr << "    --sync-gpio-path=<path>             GPIO chip device"
-                 " for the GPIO that performs the sync function\n";
-    std::cerr << "    --sync-gpio-num=<path>              GPIO number for the"
-                 " GPIO that performs the sync function\n";
-    std::cerr << std::flush;
-}
-
-const option ArgumentParser::options[] = {
-    {"path", required_argument, NULL, 'p'},
-    {"instance", required_argument, NULL, 'n'},
-    {"inventory", required_argument, NULL, 'i'},
-    {"num-history-records", required_argument, NULL, 'r'},
-    {"sync-gpio-path", required_argument, NULL, 'a'},
-    {"sync-gpio-num", required_argument, NULL, 'u'},
-    {"help", no_argument, NULL, 'h'},
-    {0, 0, 0, 0},
-};
-
-const char* ArgumentParser::optionStr = "p:n:i:r:a:u:h";
-
-const std::string ArgumentParser::trueString = "true";
-const std::string ArgumentParser::emptyString = "";
-
-} // namespace power
-} // namespace phosphor
diff --git a/power-supply/main.cpp b/power-supply/main.cpp
index a0be28c..d441dbe 100644
--- a/power-supply/main.cpp
+++ b/power-supply/main.cpp
@@ -15,10 +15,10 @@
  */
 #include "config.h"
 
-#include "argument.hpp"
 #include "device_monitor.hpp"
 #include "power_supply.hpp"
 
+#include <CLI/CLI.hpp>
 #include <phosphor-logging/log.hpp>
 #include <sdeventplus/event.hpp>
 
@@ -29,34 +29,42 @@
 
 int main(int argc, char* argv[])
 {
-    auto options = ArgumentParser(argc, argv);
+    CLI::App app{"PSU Monitor"};
 
-    auto objpath = (options)["path"];
-    auto instnum = (options)["instance"];
-    auto invpath = (options)["inventory"];
-    if (argc < 4)
+    std::string objpath{};
+    std::string instnum{};
+    std::string invpath{};
+    std::string records{};
+    std::string syncGPIOPath{};
+    std::string syncGPIONum{};
+
+    app.add_option("-p,--path", objpath, "Path to location to monitor\n")
+        ->required();
+    app.add_option("-n,--instance", instnum,
+                   "Instance number for this power supply\n")
+        ->required();
+    app.add_option("-i,--inventory", invpath,
+                   "Inventory path for this power supply\n")
+        ->required();
+    app.add_option(
+           "-r,--num-history-records", records,
+           "Number of input power history records to provide on D-Bus\n")
+        ->expected(0, 1);
+    app.add_option(
+           "-a,--sync-gpio-path", syncGPIOPath,
+           "GPIO chip device for the GPIO that performs the sync function\n")
+        ->expected(0, 1);
+    app.add_option("-u,--sync-gpio-num", syncGPIONum,
+                   "GPIO number for the GPIO that performs the sync function\n")
+        ->expected(0, 1);
+
+    try
     {
-        std::cerr << std::endl << "Too few arguments" << std::endl;
-        options.usage(argv);
-        return -1;
+        app.parse(argc, argv);
     }
-
-    if (objpath == ArgumentParser::emptyString)
+    catch (const CLI::Error& e)
     {
-        log<level::ERR>("Device monitoring path argument required");
-        return -2;
-    }
-
-    if (instnum == ArgumentParser::emptyString)
-    {
-        log<level::ERR>("Device monitoring instance number argument required");
-        return -3;
-    }
-
-    if (invpath == ArgumentParser::emptyString)
-    {
-        log<level::ERR>("Device monitoring inventory path argument required");
-        return -4;
+        return app.exit(e);
     }
 
     auto bus = sdbusplus::bus::new_default();
@@ -87,8 +95,7 @@
 
     // Get the number of input power history records to keep in D-Bus.
     long int numRecords = 0;
-    auto records = (options)["num-history-records"];
-    if (records != ArgumentParser::emptyString)
+    if (!records.empty())
     {
         numRecords = std::stol(records);
         if (numRecords < 0)
@@ -102,20 +109,15 @@
     {
         // Get the GPIO information for controlling the SYNC signal.
         // If one is there, they both must be.
-        auto syncGPIOPath = (options)["sync-gpio-path"];
-        auto syncGPIONum = (options)["sync-gpio-num"];
-
-        if (((syncGPIOPath == ArgumentParser::emptyString) &&
-             (syncGPIONum != ArgumentParser::emptyString)) ||
-            ((syncGPIOPath != ArgumentParser::emptyString) &&
-             (syncGPIONum == ArgumentParser::emptyString)))
+        if ((syncGPIOPath.empty() && !syncGPIONum.empty()) ||
+            (!syncGPIOPath.empty() && syncGPIONum.empty()))
         {
             std::cerr << "Invalid sync GPIO number or path\n";
             return -7;
         }
 
         size_t gpioNum = 0;
-        if (syncGPIONum != ArgumentParser::emptyString)
+        if (!syncGPIONum.empty())
         {
             gpioNum = stoul(syncGPIONum);
         }
diff --git a/power-supply/meson.build b/power-supply/meson.build
index 4bf1626..20fec89 100644
--- a/power-supply/meson.build
+++ b/power-supply/meson.build
@@ -1,6 +1,5 @@
 psu_monitor = executable(
     'psu-monitor',
-    'argument.cpp',
     error_hpp,
     'main.cpp',
     'power_supply.cpp',