The Third International Model-Driven Requirements Engineering (MoDRE) workshop continues to provide a forum to discuss the challenges of Model-Driven Development (MDD) for Requirements Engineering (RE). Building on the success of MDD for design and implementation, RE may benefit from MDD techniques when properly balancing flexibility for capturing varied user needs with formal rigidity required for model transformations as well as high-level abstraction with information richness. Reuse of requirements models becomes a distinct possibility with MDD and model transformations. Furthermore, requirements models may be used at runtime to govern system execution. This workshop intends to identify new challenges, discuss on-going work and potential solutions, analyze the strengths and weaknesses of MDD approaches for RE, foster stimulating discussions on the topic, and provide opportunities to apply MDD approaches for RE. In this edition of the workshop, the emphasis is on the topics of requirements reuse and requirements at runtime. The workshop is co-located with the 21st IEEE International Requirements Engineering Conference (RE 2013) in Rio de Janeiro, Brazil, in July 2013. Accepted papers will become part of the workshop proceedings and will be submitted for inclusion into the IEEE Digital Library.