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Metal-organic frameworks made from multi-metal-ion units in the shape of clusters and rods (termed dot-MOFs and rod-MOFs) are well known. Here, we introduce MOFs with multi-metallic units in the form of sheets—sheet-MOFs. We show exemplars of all three types of units based on structures containing Y³⁺, Ce³⁺, or Gd³⁺ linked by benzene-1,2,4,5-tetracarboxylate to give crystals of a dot-MOF in H₂NMe₂[Y(btec)(H₂O)] CTH-14, a sheet-MOF in [Ce₃(btec)(Hbtec)(OAc)(HCO₂)] CTH-15, and a rod-MOF in 4,4′-azopyridinium[Gd₂(btec)₂] CTH-16. Cyclic voltammetry shows that CTH-15 stabilizes Ce(IV). Given the fact that sheet-MOFs represent an intellectual advance in the evolution of MOFs, a unified approach is proposed for the topological classification of dot-, rod-, and sheet-MOFs. It is suggested that the stability of MOFs follow in the trend dot < rod < sheet. For CTH-14-16, the sheet- and the rod-MOF have …