The foot is the key prosodic category involved in constructing stress and accent patterns. There is compelling evidence for binary feet – feet that are either disyllabic or bimoraic – but no compelling evidence for feet larger than two syllables. Feet always have syllables as their constituents. While some proposals involve mora-based footing, building feet on moras unnecessarily flouts fundamental restrictions on the prosodic hierarchy. Weak Layering approaches, including the Layered Foot approach, are susceptible to the Odd-Parity Input Problem. The Odd-Parity Input Problem is a set of pathological predictions that arise from the need to achieve exhaustive binary parsing in odd-parity forms. It has two sub-problems. The first is the Odd Heavy Problem, a quirky type of quantity sensitivity where exhaustive binary parsing is achieved in odd-parity forms by parsing a single odd-numbered heavy syllable as a monosyllabic foot. The second is the Even Output Problem, where an odd-parity input is converted to an even-parity output to achieve exhaustive binary parsing. Unlike Weak Layering approaches, Weak Bracketing is not susceptible to the Odd-Parity Input Problem.