diff --git a/dbus/dbushelper.cpp b/dbus/dbushelper.cpp
new file mode 100644
index 0000000..cb847e6
--- /dev/null
+++ b/dbus/dbushelper.cpp
@@ -0,0 +1,178 @@
+/**
+ * Copyright 2017 Google Inc.
+ *
+ * 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 "dbushelper.hpp"
+
+#include "dbushelper_interface.hpp"
+#include "dbusutil.hpp"
+
+#include <phosphor-logging/log.hpp>
+#include <sdbusplus/bus.hpp>
+
+#include <map>
+#include <string>
+#include <variant>
+#include <vector>
+
+namespace pid_control
+{
+
+using Property = std::string;
+using Value = std::variant<int64_t, double, std::string, bool>;
+using PropertyMap = std::map<Property, Value>;
+
+using namespace phosphor::logging;
+
+/* TODO(venture): Basically all phosphor apps need this, maybe it should be a
+ * part of sdbusplus.  There is an old version in libmapper.
+ */
+std::string DbusHelper::getService(sdbusplus::bus::bus& bus,
+                                   const std::string& intf,
+                                   const std::string& path)
+{
+    auto mapper =
+        bus.new_method_call("xyz.openbmc_project.ObjectMapper",
+                            "/xyz/openbmc_project/object_mapper",
+                            "xyz.openbmc_project.ObjectMapper", "GetObject");
+
+    mapper.append(path);
+    mapper.append(std::vector<std::string>({intf}));
+
+    std::map<std::string, std::vector<std::string>> response;
+
+    try
+    {
+        auto responseMsg = bus.call(mapper);
+
+        responseMsg.read(response);
+    }
+    catch (const sdbusplus::exception::SdBusError& ex)
+    {
+        log<level::ERR>("ObjectMapper call failure",
+                        entry("WHAT=%s", ex.what()));
+        throw;
+    }
+
+    if (response.begin() == response.end())
+    {
+        throw std::runtime_error("Unable to find Object: " + path);
+    }
+
+    return response.begin()->first;
+}
+
+void DbusHelper::getProperties(sdbusplus::bus::bus& bus,
+                               const std::string& service,
+                               const std::string& path,
+                               struct SensorProperties* prop)
+{
+    auto pimMsg = bus.new_method_call(service.c_str(), path.c_str(),
+                                      propertiesintf, "GetAll");
+
+    pimMsg.append(sensorintf);
+
+    PropertyMap propMap;
+
+    try
+    {
+        auto valueResponseMsg = bus.call(pimMsg);
+        valueResponseMsg.read(propMap);
+    }
+    catch (const sdbusplus::exception::SdBusError& ex)
+    {
+        log<level::ERR>("GetAll Properties Failed",
+                        entry("WHAT=%s", ex.what()));
+        throw;
+    }
+
+    // The PropertyMap returned will look like this because it's always
+    // reading a Sensor.Value interface.
+    // a{sv} 3:
+    // "Value" x 24875
+    // "Unit" s "xyz.openbmc_project.Sensor.Value.Unit.DegreesC"
+    // "Scale" x -3
+
+    // If no error was set, the values should all be there.
+    auto findUnit = propMap.find("Unit");
+    if (findUnit != propMap.end())
+    {
+        prop->unit = std::get<std::string>(findUnit->second);
+    }
+    auto findScale = propMap.find("Scale");
+    auto findMax = propMap.find("MaxValue");
+    auto findMin = propMap.find("MinValue");
+
+    prop->min = 0;
+    prop->max = 0;
+    prop->scale = 0;
+    if (findScale != propMap.end())
+    {
+        prop->scale = std::get<int64_t>(findScale->second);
+    }
+    if (findMax != propMap.end())
+    {
+        prop->max = std::visit(VariantToDoubleVisitor(), findMax->second);
+    }
+    if (findMin != propMap.end())
+    {
+        prop->min = std::visit(VariantToDoubleVisitor(), findMin->second);
+    }
+
+    prop->value = std::visit(VariantToDoubleVisitor(), propMap["Value"]);
+
+    return;
+}
+
+bool DbusHelper::thresholdsAsserted(sdbusplus::bus::bus& bus,
+                                    const std::string& service,
+                                    const std::string& path)
+{
+
+    auto critical = bus.new_method_call(service.c_str(), path.c_str(),
+                                        propertiesintf, "GetAll");
+    critical.append(criticalThreshInf);
+    PropertyMap criticalMap;
+
+    try
+    {
+        auto msg = bus.call(critical);
+        msg.read(criticalMap);
+    }
+    catch (sdbusplus::exception_t&)
+    {
+        // do nothing, sensors don't have to expose critical thresholds
+        return false;
+    }
+
+    auto findCriticalLow = criticalMap.find("CriticalAlarmLow");
+    auto findCriticalHigh = criticalMap.find("CriticalAlarmHigh");
+
+    bool asserted = false;
+    if (findCriticalLow != criticalMap.end())
+    {
+        asserted = std::get<bool>(findCriticalLow->second);
+    }
+
+    // as we are catching properties changed, a sensor could theoretically jump
+    // from one threshold to the other in one event, so check both thresholds
+    if (!asserted && findCriticalHigh != criticalMap.end())
+    {
+        asserted = std::get<bool>(findCriticalHigh->second);
+    }
+    return asserted;
+}
+
+} // namespace pid_control