Storing Variables for Global Use In Application

I am having some trouble with a simple problem of storing variables within my program. I am retrieving settings from within an XML file, which is working fine. But I need to store the variables in my program for the duration of its execution. I figured I need to store them in a separate .cs (Class) file within the project, possibly as Attributes. Then use the Set and Get methods to control the values. I do want the values to be stored in a separate class of their own so that they can be controlled and used by methods in several other classes. * Am I approaching the problem the correct way? * If I do the following, will the values remain set, unless modified, until the program terminates? // Start of Settings Class using System; namespace Settings { // Main class, which will have several sub-classes internal class clsMain { // Sub-class, which is one of several classes within the Main class internal class clsSetting : Attribute { protected double dValue; public double DoubleValue { get{return dValue;} set{dValue = value;} } protected string sValue; public double StringValue { get{return sValue;} set{sValue = value;} } } } } // End of Settings Class // Sample code used in different class, within a different .cs file in the project private clsMain.clsSetting Setting = new clsMain.clsSetting(); // Store values in Settings Setting.DoubleValue = 12345; Setting.StringValue = "TestValue"; // Retrieve values from Settings MessageBox.Show("DoubleValue = " + Setting.DoubleValue.ToString()); MessageBox.Show("StringValue = " + Setting.StringValue());