Ongoing education and training play an important role in the professional life. Parallel, in the geospatial and IT arena as well in the political discussion and legislation Open Source solutions, open data proliferation, and the use of open standards have an increasing significance. Based on the Memorandum of Understanding between International Cartographic Association, OSGeo Foundation, and ISPRS this development led to the implementation of the ICA-OSGeo-Lab initiative. Its mission "Making geospatial education and opportunities accessible to all" initiated the idea for a framework for a worldwide applicable Open Source certification approach. The development of the framework presented here is based on the analysis of diverse bodies of knowledge concepts, i.e., the Geospatial Technology Competency Model (GTCM) which provides a US American oriented list of the knowledge, skills, and abilities. In addition to this analysis the geospatial community was integrated by an online survey and interviews with experts in different countries about Open Source usage and certification. In the developed certification framework each certificate is described by pre-conditions, scope and objectives, course content, recommended software packages, target group, expected benefits, and the methods of examination. Examinations can be flanked by proofs of professional career paths and achievements which need a peer qualification evaluation with recertification after a couple of years. The concept seeks the accreditation by the OSGeo Foundation and international support by a group of geospatial scientific institutions to achieve wide and international acceptance.