Both 'primary' and 'secondary' sources were used to create the data base for this study. Data from primary sources was obtained by working with informants or analysing language use; data from secondary sources was obtained from descriptions of languages (including extant grammars and work specialising in nominalizations). (For the terms 'primary' vs. 'secondary', see Dahl 1985: 36). There were two kinds of difficulties in obtaining relevant data: (1) those connected with determining the frame (Bell 1978: 126) for the study, that is, connected with finding out which languages have action nominal constructions; and (2) those connected with gathering information about the internal syntax of such constructions. Below I will give some examples of these problems and show some of the advantages and disadvantages of using 'primary' and 'secondary' data.