AbstractThought sequences are ordered series of verbal-like expressions that pass spontaneously through one's mind and which are characterised by well-demarcated beginnings and ends. The present paper notes the significance of and interest in thought sequences and presents a framework for their analysis. Given the scope of the enterprise, different levels of analysis are noted which set the boundaries for the present investigation, and define guidelines for further research. Here, the focus of interest is the structural (as distinct from either functional or computational) relationships between pairs of consecutive expressions. The informational bases for these relationships are reviewed and a typology of them is drawn. The typology reveals marked internal structure and it suggests that the variety of couplings of thought sequences constitutes a space spanned by a small number of variables. Methodological issues regarding the use of introspection in cognitive research are also discussed.