This paper offers a comprehensive and critical review of the most significant studies on the possible alternation between two specific encodings that can express, in a generic sense, the Manner in which a verbal process is developed: adverbial expressions (ADV) and Secondary Predicates (SP). The main types of SP/ADV to be addressed here are those which are Subject and/or event oriented. Both general and typological works will be taken into account, as well as others more focused on the Latin language; the central criterion of the study will essentially be to distinguish and analyse approaches which are more or less favourable to seeing the two types of constituents as equivalent. A section devoted to the work of one of the Latinists who has contributed most specifically and notably to the issue under discussion (H. Pinkster) will also be included. Following a critical review of the criteria which have the greatest explanatory potential for explaining the issue, some analytical approaches will be proposed which are as objective as possible for a subsequent corpus study; these criteria include parameters pertaining to different linguistic levels: syntax, lexical-semantics, pragmatics, etc.: their application — here only tentatively discussed — will provide clear and measurable results on the problem and on those questions arising from the critical review itself.