diff --git a/README.md b/README.md
index 559984a22..fcaeff363 100644
--- a/README.md
+++ b/README.md
@@ -88,6 +88,77 @@ If you already use one of these libraries in your project than just use the spec
 ```
 </details>
 
+### Configuration
+
+<details>
+  <summary>via jollyday.properties (click to expand)</summary>
+
+  ### Providing own properties
+
+  The configuration resides within the `jollyday.properties` and can be overridden by:
+
+  **URLs**  
+  Specifying a comma separated list of **URLs** with the system property `de.focus_shift.jollyday.config.urls` which point
+  to properties files to overload the basic properties.
+
+  ```bash
+  -Dde.focus_shift.jollyday.config.urls=file:/some/path/new.properties,http://myserver/some/path/further.properties,jar:file:myLibrary.jar!/my.properties
+  ```
+
+  **Classes**  
+  Specifying a comma separated list of **classes** which implement the `ConfigurationProvider` interface with the
+  system property `de.focus_shift.jollyday.config.providers`. This will overload the basic and the URL specified properties.
+
+  ```bash
+  -Dde.focus_shift.jollyday.config.providers=some.package.name.MyConfigurationProvider,some.other.package.AnotherConfigurationProvider
+  ```
+
+  **URLs and Classes**  
+  The order of loading properties is Base -> URLs -> ConfigurationProvider.
+
+
+  ### Providing own implementations
+
+  **Manager implementation**  
+  A manager implementation extends the abstract `HolidayManager` class and does the actual holiday parsing.
+  The basic API properties are used to define the manager implementation class used for the specific
+  country the manager is created for.
+  
+  ```properties
+  manager.impl=de.focus_shift.jollyday.core.impl.DefaultHolidayManager
+  ```
+  
+  This configuration defines a manager implementation class used as a default for every country. You can define a
+  manager implementation on a per country base.
+  
+  ```properties
+  manager.impl=de.focus_shift.jollyday.core.impl.XMLManager
+  manager.impl.us=de.focus_shift.jollyday.core.impl.MyXMLManager
+  ```
+  
+  This will let the `MyXMLManager` class be used for calculating US holidays and the `XMLManager` for all other countries.
+
+  **Parser implementation**  
+  A parser implementation is used for parsing the XML file content. There are several parsers configured depending on the class to parse the info from.
+  
+  ```properties
+  parser.impl.de.focus_shift.jollyday.core.spi.Fixed                       = de.focus_shift.jollyday.core.parser.impl.FixedParser
+  parser.impl.de.focus_shift.jollyday.core.spi.FixedWeekdayInMonth         = de.focus_shift.jollyday.core.parser.impl.FixedWeekdayInMonthParser
+  parser.impl.de.focus_shift.jollyday.core.spi.IslamicHoliday              = de.focus_shift.jollyday.core.parser.impl.IslamicHolidayParser
+  parser.impl.de.focus_shift.jollyday.core.spi.ChristianHoliday            = de.focus_shift.jollyday.core.parser.impl.ChristianHolidayParser
+  parser.impl.de.focus_shift.jollyday.core.spi.RelativeToFixed             = de.focus_shift.jollyday.core.parser.impl.RelativeToFixedParser
+  parser.impl.de.focus_shift.jollyday.core.spi.RelativeToWeekdayInMonth    = de.focus_shift.jollyday.core.parser.impl.RelativeToWeekdayInMonthParser
+  parser.impl.de.focus_shift.jollyday.core.spi.FixedWeekdayBetweenFixed    = de.focus_shift.jollyday.core.parser.impl.FixedWeekdayBetweenFixedParser
+  parser.impl.de.focus_shift.jollyday.core.spi.FixedWeekdayRelativeToFixed = de.focus_shift.jollyday.core.parser.impl.FixedWeekdayRelativeToFixedParser
+  parser.impl.de.focus_shift.jollyday.core.spi.EthiopianOrthodoxHoliday    = de.focus_shift.jollyday.core.parser.impl.EthiopianOrthodoxHolidayParser
+  parser.impl.de.focus_shift.jollyday.core.spi.RelativeToEasterSunday      = de.focus_shift.jollyday.core.parser.impl.RelativeToEasterSundayParser
+  ```
+
+  The configuration property name starts with `parser.impl` and finishes with the XML class name.
+  The value is the parser implementation class name which implements the `HolidayParser` interface. 
+
+</details>
+
 ### Examples
 
 <details>
diff --git a/jollyday-core/src/main/java/de/focus_shift/jollyday/core/configuration/ConfigurationProvider.java b/jollyday-core/src/main/java/de/focus_shift/jollyday/core/configuration/ConfigurationProvider.java
index 01151d769..d0811777c 100644
--- a/jollyday-core/src/main/java/de/focus_shift/jollyday/core/configuration/ConfigurationProvider.java
+++ b/jollyday-core/src/main/java/de/focus_shift/jollyday/core/configuration/ConfigurationProvider.java
@@ -12,13 +12,13 @@ public interface ConfigurationProvider {
    * {@link ConfigurationProvider} implementations to use for jollyday
    * configuration.
    */
-  String CONFIG_PROVIDERS_PROPERTY = "config.providers";
+  String CONFIG_PROVIDERS_PROPERTY = "de.focus_shift.jollyday.config.providers";
 
   /**
    * System property to define URLs to overriding jollyday configuration
    * files.
    */
-  String CONFIG_URLS_PROPERTY = "config.urls";
+  String CONFIG_URLS_PROPERTY = "de.focus_shift.jollyday.config.urls";
 
   /**
    * @return the configuration properties for jollyday.
diff --git a/jollyday-core/src/test/java/de/focus_shift/jollyday/core/configuration/URLConfigurationProviderTest.java b/jollyday-core/src/test/java/de/focus_shift/jollyday/core/configuration/URLConfigurationProviderTest.java
index e76627804..0fbfdc010 100644
--- a/jollyday-core/src/test/java/de/focus_shift/jollyday/core/configuration/URLConfigurationProviderTest.java
+++ b/jollyday-core/src/test/java/de/focus_shift/jollyday/core/configuration/URLConfigurationProviderTest.java
@@ -42,7 +42,7 @@ void testPutConfigurationWithPropertyWithCorrectURL() {
     System.setProperty(CONFIG_URLS_PROPERTY, "file:./src/test/resources/url.load.properties");
     final Properties props = sut.getProperties();
     assertThat(props).isNotEmpty();
-    assertThat(props.getProperty("manager.impl.test")).isEqualTo("de.jollyday.impl.DefaultHolidayManager");
+    assertThat(props.getProperty("manager.impl.test")).isEqualTo("de.focus_shift.jollyday.impl.DefaultHolidayManager");
     assertThat(props.getProperty("manager.impl")).isEqualTo("ManagerOverloaded");
   }
 }
diff --git a/jollyday-core/src/test/resources/url.load.properties b/jollyday-core/src/test/resources/url.load.properties
index 17a804d90..06a617431 100644
--- a/jollyday-core/src/test/resources/url.load.properties
+++ b/jollyday-core/src/test/resources/url.load.properties
@@ -1,5 +1,5 @@
 # Specify Manager implementation on a per country base
 # if there is country based implementation specified this
 # will be used by default.
-manager.impl.test = de.jollyday.impl.DefaultHolidayManager
+manager.impl.test = de.focus_shift.jollyday.impl.DefaultHolidayManager
 manager.impl      = ManagerOverloaded
diff --git a/jollyday-tests/src/test/java/de/focus_shift/jollyday/tests/HolidayManagerTest.java b/jollyday-tests/src/test/java/de/focus_shift/jollyday/tests/HolidayManagerTest.java
index 753562876..327d55f6d 100644
--- a/jollyday-tests/src/test/java/de/focus_shift/jollyday/tests/HolidayManagerTest.java
+++ b/jollyday-tests/src/test/java/de/focus_shift/jollyday/tests/HolidayManagerTest.java
@@ -88,13 +88,13 @@ private static Stream<Arguments> firstLevel() {
 
   @Test
   void ensureToInstantiateHolidayManagerImplementationBasedOnCountry() {
-    System.setProperty("config.urls", "file:./src/test/resources/test.app.properties");
+    System.setProperty("de.focus_shift.jollyday.config.urls", "file:./src/test/resources/test.app.properties");
 
     HolidayManager.setManagerCachingEnabled(false);
     assertThat(HolidayManager.getInstance(create("test"))).isInstanceOf(JapaneseHolidayManager.class);
     HolidayManager.setManagerCachingEnabled(true);
 
-    System.clearProperty("config.urls");
+    System.clearProperty("de.focus_shift.jollyday.config.urls");
   }
 
   @Test