Membership and photometry of the open cluster IC 4756 Probabilities of membership, based on relative proper motions, for 464stars in the field of IC 4756 are given. The cluster proper motiondispersion (m.e.) of 0.09 sec of arc yields 173 probable members.Photographic UBV magnitudes of 471 stars in the field are presented. Thecolor excess of IC 4756 is E(B-V) equal to 0.19 min; the apparentdistance modulus equals 8.5 min, corresponding to the true distance of400 pc. The membership probabilities of 6 blue stragglers and of thesupergiant HD 172365 (F9 Ib) are discussed.