This doctoral seminar is intended for PhD students in any track (Development or International Economics) of the doctoral curriculum. The course will present models and empirical methods commonly used to tackle questions on firm behaviour, competition and market structure. In particular, the course will revise structural approaches to demand estimation, cost and technology estimation, entry decisions, bargaining, pricing and contracting problems (please note this list of specific topics might change). Emphasis will be placed on the presentation of the theoretical models, econometric techniques and, time permitting, coding exercises that constitute the core of structural empirical work on applied microeconomics. Applications in development and trade will be used as guiding examples.