Complex systems and their phenomena are ubiquitous as they can be

found in biology, finance, the humanities, management sciences,

medicine, physics and similar fields.For many problems in these fields, there are no conventional ways to

mathematically or analytically solve them completely at low cost. On

the other hand, nature already solved many optimization problems

efficiently. Computational intelligence attempts to mimic

natureinspired problemsolving strategies and methods.These strategies can be used to study, model and analyze complex

systems such that it becomes feasible to handle them. Key areas of

computational intelligence are artificial neural networks,

evolutionary computation and fuzzy systems.As only a few researchers in that field, Rudolf Kruse has contributed

in many important ways to the understanding, modeling and application

of computational intelligence methods. On occasion of his 60th

birthday, a collection of original papers of leading researchers in

the field of computational intelligence has been collected in this

volume.