Aluminum ion (Al 3 + ) is known to affect markedly a wide variety of biological systems, and the presence of Al 3 + in humans has been linked to a number of diseases. As the role of Al 3 + in human disease clearly has its origins in Al 3 + coordination chemistry, and since ATP may well serve as the predominant binder of Al 3 + in many cells, it is important to understand speciation in systems containing Al 3 + ion and nucleoside di- and triphosphates (especially ADP and ATP). There are also a large number of proteins which require nucleoside phosphates as substrates or are regulated by nucleoside phosphates, and Al 3 + ion can potentially interfere with the normal functions of these proteins. The objective of this review is to present the current state of our understanding of aluminum complexation with nucleoside di- and triphosphates and to indicate possible consequences of Al 3 + complexation with proteins. Much of the current knowledge has been revealed by comprehensive potentiometric titration and multinuclear nuclear magnetic resonance analyses. Computer calculations have also played an important role in expanding our understanding of Al 3 + complexation with nucleoside phosphates.