Proceedings of the International Conferences LEAP'11 (Low Energy Antiproton Physics) held from April 27th to May, 1st  2011 in Vancouver, Canada and hosted by TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics. Now the research in exotic atoms has a remarkable history of more than 50 years. Enormous success in the understanding of fundamental interactions and symmetries resulted from the research on these tiny objects at the femtoscale. This volume contains research papers on recent achievements and future opportunities of this highly interdisciplinary field of atomic, nuclear, and particle physics. The Proceedings are structured according to the conference session topics. It is directed to researchers in the field and advanced students.