Combinatorics 86 : proceedings of the International Conference on Incidence Geometries and Combinatorial Structures Passo della Mendola Trento Italy 30 June 5 July 1986 Recent developments in all aspects of combinatorial and incidence geometry are covered in this volume including their links with the foundations of geometry graph theory and algebraic structures and the applications to coding theory and computer science. Topics covered include Galois geometries blocking sets affine and projective planes incidence structures and their automorphism groups. Matroids graph theory and designs are also treated along with weak algebraic structures such as near rings near fields quasi groups loops hypergroups etc. and permutation sets and groups. The vita