Notes on Harmonic Maps

This is set of notes prepared for the Summer School on non-Abelian Hodge theory in Abbaye de Saint-Jacut de la Mer June, 6-19, 2022. We cover the following topics: Lecture 1. Harmonic Maps Between Riemannian Manifolds Lecture 2. Existence and Regularity Lecture 3. Pluriharmonic Maps and the Siu-Sampson Formula Lecture 4. Donaldson Corlette Theorem