This document provides an overview of security for performance in construction contracts, including different forms of security like bank guarantees, letters of credit, and performance bonds. It discusses key cases like Woodhall Limited v The Pipeline Authority that established the autonomy principle for bank guarantees, meaning they are payable on demand regardless of disputes between the parties. The document outlines exceptions to the autonomy principle such as fraud, statutory provisions, and express contractual exclusions. It also analyzes relevant clauses from the case Rejan Constructions Pty Ltd v Manningham Medical Centre Pty Ltd regarding when a party can have recourse to security or retention money.