Methods of using microorganisms to make chemicals and fuels, including carboxylic acids, alcohols, hydrocarbons, and their alpha-, beta-, and omega-functionalized derivatives are described. Native or engineered thiolases are used condense a growing acyl-ACP and acetyl-ACP in combination with type II fatty acid synthesis. The resulting fatty acid biosynthesis cycle has an ATP yield analogous to the functional reverse β-oxidation cycle.