This document discusses several techniques for estimating software costs: expert judgement, pricing to win, estimation by analogy, bottom-up, top-down, and algorithmic cost modeling. Expert judgement involves consulting experts and iterating until agreement. Pricing to win bases the estimate only on the customer's budget. Estimation by analogy compares a new project to similar past projects. Bottom-up and top-down respectively estimate from components or overall functionality. Algorithmic cost modeling uses mathematical equations based on historical data.