In the last decade we have witnessed an increased interest in the synthesis of co-crystals involving active pharmaceutical ingredients (API), with the aim to produce valuable new materials with improved solubility, dissolution rate, stability and bioavailability.1 Crystal engineering and supramolecular synthesis are being widely explored to obtain new crystalline pharmaceutical formulations from known APIs and a benign additive used as a co-crystal former (CCF). Carboxylic and dicarboxylic acids have emerged as the leading candidates among CCFs used for this purpose. However, an increasing desire to develop a wider library of CCFs for fine tuning crystalline drug properties has motivated the search for new CCFs, capable of forming multiple-component pharmaceutical solids with APIs; namely, co-crystal, organic salts and their hydrates. As part of our ongoing efforts toward the crystal engineering of new multicomponent pharmaceutical solids, we carried out the systematic investigation of the interaction of p-aminobenzoic acid (PABA) with azamacrocycles having different ring sizes (12, 14, 18 atoms in the ring) and a variable number of incorporated nitrogen atoms (n=1-4), which are predisposed to interactions with a carboxylic acid. PABA is an important biological molecule, being an essential bacterial growth factor involved in the synthesis of pteroylglutamic acid (folic acid), which has been shown to form in vitro in the presence of ATP and Mg2+. In another unrelated application, PABA and its ether are used as sunscreen agents. As such, PABA is one of the most interesting small molecules for use in syntheses based on hydrogen bonding interactions with a variety of organic acids and bases. Furthermore, due to the presence of two favorably arranged functional groups, PABA can generate advantageous hydrogen-bonded arrays. Crystallographic studies of four novel supramolecular multicomponent complexes with the compositions (H2teta).(PABA)2 .H2O, (H2cyclen).(PABA)2 .2H2O, (H-aza-18C6).(PABA).3H2O, (H2-diaza12C4).(PABA)2 .2H2O, reveal that they are all organic salts formed due to proton transfer from the carboxylic acid group of PABA to the amino group of the macrocycle, and thus are comprised of a PABA anion, a macrocyclic mono- or dication and a variable number of water molecules. In all complexes, the cations and anions are associated via NH+…O- charge-assisted hydrogen bonds, while the PABA anions self-assemble into helical chains due to interactions between their primary amino and carboxylate functionalities. Water molecules add diversity into the supramolecular architecture and offer promise in regards to fine tuning bulk solubility.formula(H2teta) (PABA)2 .H2Oformula(H2cyclen) (PABA)2 .2H2O