Description:This book constitutes the refereed proceedings of the 6th International Conference on Mathematical Knowledge Management, MKM 2007, and the 14th Symposium on the Integration of Symbolic Computation and Mechanized Reasoning, Calculemus 2006, held in Hagenberg, Austria in June 2007 as events of the RISC Summer 2007, organized by the Research Institute for Symbolic Computation. The 10 revised full papers from 23 submissions for Calculemus 2007 and 19 revised full papers, plus abstracts of 2 invited talks, selected from 52 submissions to MKM 2007 were carefully reviewed and selected for a joint presentation in the book. The papers cover different aspects of traditional branches in CS such as computer algebra and theorem proving, as well as newly emerging ones such as user interfaces, knowledge management, and theory exploration. Thus facilitating the development of integrated mechanized mathematical assistants.