Valency patterns and valency orientation have been frequent topics of research under different
perspectives often poorly connected. Diachronic studies on these topics is even less
systematic than synchronic ones. The papers in this book bring together two strands of research
on valency i.e. the description of valency patterns as worked out in the Leipzig Valency
Classes Project (ValPaL) and the assessment of a language's basic valency and its possible
orientation. Notably the ValPaL does not provide diachronic information concerning the valency
patterns investigated: one of the aims of the book is to supplement the available data with
data from historical stages of languages in order to make it profitably exploitable for
diachronic research. In addition new research on the diachrony of basic valency and valency
alternations can deepen our understanding of mechanisms of language change and of the
propensity of languages or language families to exploit different constructional patterns
related to transitivity.
