diff --git a/src/config.js b/src/config.js
index ed13e5a..2f6138f 100644
--- a/src/config.js
+++ b/src/config.js
@@ -16,9 +16,10 @@ export default class Config {
 	/**
 	 * Creates an instance of the {@link ~Config} class.
 	 *
-	 * @param {Object} [configurations] The initial configurations to be set.
+	 * @param {Object} [configurations] The initial configurations to be set. Usually, provided by the user.
+	 * @param {Object} [defaultConfigurations] The default configurations. Usually, provided by the system.
 	 */
-	constructor( configurations ) {
+	constructor( configurations, defaultConfigurations ) {
 		/**
 		 * Store for the whole configuration.
 		 *
@@ -27,6 +28,11 @@ export default class Config {
 		 */
 		this._config = {};
 
+		// Set default configuration.
+		if ( defaultConfigurations ) {
+			this.define( defaultConfigurations );
+		}
+
 		// Set initial configuration.
 		if ( configurations ) {
 			this._setObjectToTarget( this._config, configurations );
diff --git a/tests/config.js b/tests/config.js
index 1e8defb..5963171 100644
--- a/tests/config.js
+++ b/tests/config.js
@@ -23,7 +23,7 @@ describe( 'Config', () => {
 		} );
 	} );
 
-	describe( 'constructor', () => {
+	describe( 'constructor()', () => {
 		it( 'should set configurations', () => {
 			expect( config.get( 'creator' ) ).to.equal( 'inline' );
 			expect( config.get( 'language' ) ).to.equal( 'pl' );
@@ -41,9 +41,81 @@ describe( 'Config', () => {
 			// No error should be thrown.
 			config = new Config();
 		} );
+
+		it( 'should set default parameters', () => {
+			const defaultConfig = {
+				foo: 1,
+				bar: 2,
+			};
+
+			config = new Config( {}, defaultConfig );
+
+			expect( config.get( 'foo' ) ).to.equal( 1 );
+			expect( config.get( 'bar' ) ).to.equal( 2 );
+		} );
+
+		it( 'passed parameters should override default parameters', () => {
+			const defaultConfig = {
+				foo: 1,
+				bar: 2,
+			};
+
+			config = new Config( {
+				foo: 10,
+			}, defaultConfig );
+
+			expect( config.get( 'foo' ) ).to.equal( 10 );
+			expect( config.get( 'bar' ) ).to.equal( 2 );
+		} );
+
+		it( 'should work with deeper objects', () => {
+			const defaultConfig = {
+				a: {
+					first: 1,
+					second: 2
+				},
+				b: {
+					foo: {
+						first: 1,
+						second: 2,
+					}
+				}
+			};
+
+			const parameters = {
+				a: {
+					third: 3
+				},
+				b: {
+					foo: {
+						first: 3,
+						third: 1
+					}
+				},
+				custom: 'foo'
+			};
+
+			config = new Config( parameters, defaultConfig );
+
+			expect( config.get( 'a' ) ).to.deep.equal( {
+				first: 1,
+				second: 2,
+				third: 3
+			} );
+
+			expect( config.get( 'b' ) ).to.have.key( 'foo' );
+
+			expect( config.get( 'b.foo' ) ).to.deep.equal( {
+				first: 3,
+				second: 2,
+				third: 1
+			} );
+
+			expect( config.get( 'custom' ) ).to.equal( 'foo' );
+		} );
 	} );
 
-	describe( 'set', () => {
+	describe( 'set()', () => {
 		it( 'should set configurations when passing objects', () => {
 			config.set( {
 				option1: 1,
@@ -158,7 +230,7 @@ describe( 'Config', () => {
 		} );
 	} );
 
-	describe( 'define', () => {
+	describe( 'define()', () => {
 		it( 'should set configurations when passing objects', () => {
 			config.set( {
 				option1: 1,
@@ -252,7 +324,7 @@ describe( 'Config', () => {
 		} );
 	} );
 
-	describe( 'get', () => {
+	describe( 'get()', () => {
 		it( 'should retrieve a configuration', () => {
 			expect( config.get( 'creator' ) ).to.equal( 'inline' );
 		} );