This chapter contains sections titled: Introduction Indentation Contact Radius and Contact Force Indentation and Contact Radius Indentation and Contact Force Inverted Functions Contact Force and Contact Radius Contact Radius and Indentation Contact Force and Indentation Limits of Adhesion Parameters Contact Pressure Maximum Contact Pressure Distribution of Contact Pressure Lennard–Jones Potential Total Force and Indentation Push-in Region Push-in Region in the Absence of Adhesion Push-in Region in the Presence of Adhesion Pull-out Region Pull-out Region in the Absence of Adhesion Pull-out Region in the Presence of Adhesion Hysteresis Loop Exercises for Chapter 5 References