α-synuclein is one of a family of proteins whose function remains unknown. This protein has become linked to a number of neurodegenerative disease although its potential causative role in these diseases remains mysterious. In diseases such as Parkinson's disease and Lewy body dementias, α-synuclein becomes deposited in aggregates termed Lewy bodies. Also, some inherited forms of Parkinson's diseases are linked to mutations in the gene for α-synuclein. Studies have mostly focussed on what causes the aggregation of the protein but, like many amyloidogenic proteins associated with a neurodegenerative disorder, this protein has now been suggested to bind copper. This finding is currently controversial. This review examines the evidence that α-synuclein is a copper binding protein and discusses whether this has any significance in determining the function of the protein or whether copper binding is at all necessary for aggregation.