In this paper we investigate the boundary behaviour of minimal surfaces in a wedge which are either of class ℐ (Γ, ℱ) or of class ℰ(Γ, ℱ) Here Γ denotes a Jordan curve in ℝ 3 whose endpoints lie on a support surface ℱ which is assumed to be the boundary of a wedge. Then, roughly speaking, ℐ (Γ, ℱ) denotes the set of disk-type minimal surfaces which are stationary in 〈 Γ, ℐ 〉 and whose free traces on ℱ intersect the edge ℒ of the wedge “trans versally”, while ℰ(Γ, ℱ) denotes the class of corresponding surfaces whose free traces attach to ℒ in full intervals. We derive asymptotic expansions of X w and N w where X(w), w ≠ B, is a minimal surface of class ℐ(Γ, ℱ) or ℰ(Γ, ℱ), and N(w) denotes the Gauss map corresponding to X. In forthcoming papers we plan to investigate existence and uniqueness questions for minimal surfaces in a wedge. We would like to thank Gudrun Turowski for carefully reading our manuscript and for critical remarks.