I consider the possibility that the observed quarks and leptons (and their N = 1 SUSY partners) live in a Kahler coset space G/H with H e SU(3) × SU(2) × U(1). This uniquely points towards an appropriate complex (non-compact) extension of the coset space E7/SU(3) × SU(2) × U(1)4 in which there is room for three usual chiral families plus a fourth ``mirror'' family. The SU(5) subgroup of E7 may by gauged to give the GUT of Georgi and Glashow which is spontaneously broken down to the standard model. The Kahler manifold may in principle be coupled to N = 1 supergravity originating a realistic ``SUGRA GUT''. It is finally speculated about the origin of the hierarchy of quark and lepton masses which is suggested to be connected to a possible ``tumbled'' structure of the manifold.