The arrangement of Catullus’ Carmina is one of those controversial issues that in-cite respectable commentators to take up extreme positions. In 1914, the German scholar Bernhard Schmidt described the collection as ‘a wild chaos’. Forty-five years later, his compatriot Otto Weinreich riposted with the laconic statement: ‘Chaos? Cosmos!’ Former attempts to detect a structure in the collection were based on rather subjective assumptions. While translating Catullus' poetry into Dutch, Dr Claes detected an objective foundation: the principle of concatenation, i.e. the recurrence of motifs and phrases in consecutive poems. The generality of this phenomenon proves that the poet conceived of the Carmina as a coherent collection, in which the poems fit like links in a chain. The discovery of this coherence suggests a new reading of Catullus, which has also implications for the constitution of the text.