Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a distinct form of hereditary early-onset spastic ataxia related to progressive degeneration of the cerebellum and spinal cord. Following the description of the first patients in 1978, the gene responsible has been mapped and identified. It was also shown that the disease occurred worldwide with more than 70 mutations and diverse phenotypes. Because of the random partition of these mutations in the SACS gene particularly on the largest exon nine, and due to the significant clinical variability between patients described in different countries, it has been difficult to establish a genotype-phenotype correlation for the disease. This paper reviews the broad clinical features and the various molecular aspects of ARSACS, reported over the last 30 years highlighting the difficulty of finding correlations.