In the Bi2O3 MO-P2O5 ternary system, the commonly observed sizable 1D ribbon-like units have been extended to their 2D infinite end member, leading to the novel tailormade Bi4MO4(PO4)(2) compounds. It contains planar [Bi2O2](2+) derivatives, separated by two slabs of PO4, which create channels hosting the M2+ cations (M = Mg, Zn). For both compounds, supercell orderings occur comparatively to the predicted ideal crystal structure (V-Mg = 2V(ideal) and V-Zn = 8V(ideal)). In the Mg case a transition into the ideal lattice occurs above 450 degrees C. In spite of the conceptual assembly of 2D motifs, the final architecture is three-dimensional due to strong interbonds. Thus, our work gives new insights on the possibility for versatile organization of original secondary building units (SBUs) able to self-assemble into predicted structural edifices. single-crystal and powder XRD versus temperature, high-temperature P-31 NMR, as well as transmission electron microscopy were used for structural characterization. Preliminary electric characterization is also reported.