Thisvolumecontainstheinvitedandregularpaperspresentedat TCS 2010,the 6thIFIP International Conference on Theoretical Computer Science, organised by IFIP Tech- cal Committee 1 (Foundations of Computer Science) and IFIP WG 2.2 (Formal - scriptions of Programming Concepts) in association with SIGACT and EATCS. TCS 2010 was part of the World Computer Congress held in Brisbane, Australia, during September 20?23, 2010 ( ). TCS 2010 is composed of two main areas: (A) Algorithms, Complexity and Models of Computation, and (B) Logic, Semantics, Speci?cation and Veri?cation. The selection process led to the acceptance of 23 papers out of 39 submissions, eachofwhichwasreviewedbythreeProgrammeCommitteemembers.TheProgramme Committee discussion was held electronically using Easychair. The invited speakers at TCS 2010 are: Rob van Glabbeek (NICTA, Australia) Bart Jacobs (Nijmegen, The Netherlands) Catuscia Palamidessi (INRIA and LIX, Paris, France) Sabina Rossi (Venice, Italy) James Harland (Australia) and Barry Jay (Australia) acted as TCS 2010 Chairs. We take this occasion to thank the members of the Programme Committees and the external reviewers for the professional and timely work; the conference Chairs for their support; the invited speakers for their scholarly contribution; and of course the authors for submitting their work to TCS 2010.