The scenario which I want to propose does not aspire to solve the eternal "chicken or egg" problem in the ontogeny of speech. I assume the problem to be unresolvable and, moreover, to be largely irrelevant to the discussion of a probable synchronic scenario of structure creation in phonology. Also interpretations of diachrony are immune to the "question of origin", since both A®B and B®A changes are observable, and the best one can do is to state the preferred direction. Within so sketched orientation the claim will be made that rhythmic preferences form the skeleton for phonological structures. This is well evidenced both in first language acquisition with a foot as the first unit acquired and in other areas of external evidence, for instance in aphasia or phonostylistics with rhythmicization towards a simple trochaic foot. Foot-timing is a default unmarked rhythm. Typologically, languages diverge from the default either in the direction of prototypical stress-timing or in the direction of prototypical beat-timing.  Four basic language types with respect to timing can be arrived at: prototypical beat-timing (PBT), non-prototypical beat-timing (NPBT), non-prototypical stress-timing (NPST) and prototypical stress-timing (PST). Each type will be characterised with reference to eleven features predicted to be exponents and/or denominators of a particular rhythmic type. The relevant principles and units of Beats-and-Binding Phonology will be introduced as a necessary background for the enunciation of the rhythmic scenario.