The discovery of a Higgs particle by the LHC experiments has launched the exploration of electroweak symmetry breaking and potentially opened a window into beyond- Standard Model physics such as an extended Higgs sector, anomalous Higgs boson production mechanisms, or rare Higgs boson decay modes. Such discoveries would represent a smoking gun for an extended Higgs sector, and could have long-reaching implications on our understanding on how Nature works at its most fundamental level, including connections with dark matter and other cosmological problems. This represents an exciting and broad research program, complementary to precise measurements of Higgs boson couplings at the LHC and future e+/e- and/or pp colliders. The primary goal of this workshop is to bring together experts from the theoretical and experimental communities for a joint brainstorming on the status of this research, identify areas for improvements, as well as set new promising directions, ahead of the start of the LHC run at 13/14 TeV. The topics that will be covered include: - Higgs coupling measurements status/prospects (LHC and future e+/e- and/or pp colliders) and interplay with searches for a BSM Higgs sector - searches for anomalous Higgs production mechanisms (top partners, SUSY decay chains, di-Higgs, etc) - rare Higgs decays (invisible, SUSY particles, long-lived particles, etc) - direct searches for low mass (pseudo-)scalars (nMSSM, etc) - direct searches for heavy Higgs bosons (2HDM, doubly-charged, etc) - probing CP violation in the Higgs sector - role of precision physics in constraining a BSM Higgs sector (EW observables, heavy-flavor measurements, intensity frontier) - Effective Field Theory for a BSM Higgs sector - application of advanced experimental tools to BSM Higgs searches (jet substructure, jet charge, color flow, matrix-element method, etc) - connections of a BSM Higgs sector with dark matter and other cosmological problems The workshop will take place at the Centro de Ciencias de Benasque Pedro Pascual, located in Benasque (Spain), between April 6 and April 18, 2014. Benasque is a beautiful village with a famous ski resort, located in the heart of the Pyrenees, close to the Spanish border with France. In addition to the auditorium, the Center offers desk space, ubiquitous black boards and several meeting areas. To ensure a productive workshop, attendance will be limited to a maximum of 70 participants. In addition, the meeting agenda will be kept light, leaving plenty of time for discussion among participants, in the spirit of the Les Houches workshops.