Rationale In this contribution, we explore the interaction between speaker-and listener-specific behaviour in the encoding and decoding of prosodic categories� Note that this is different from exploring the link between speaker-and listener-specific behaviour, as in the studies by  Perkell et al� (2004a,b)  cited above, in which subjects participated in both a production and a perception task� Their results showed that some individuals produce contrasts more accurately than others, that some individuals discriminate contrasts more precisely than others, and that accurate speakers are also precise listeners (see Figure  1 )� This methodology is particularly suited for documenting how good individuals are at producing and perceiving contrasts -that is, at profiling the "best speakers" and "best listeners", somehow assuming that there is a phonetic equivalent of the blood-type notions of "universal donors" and "universal receivers"� Our aim is to show that not only some speakers might be generally more accurate and thus more intelligible than others, but also that some speakers might produce contrasts in a way that make them easily intelligible to some particular listeners, but not to others� This would document an interaction, rather than a link, between specificity in production and perception� Figure  2  sums up the three potential scenarios� The behaviour of speakers and listeners could be independent, it could be linked or it could interact� In each panel, individuals are represented by nodes� Listeners are represented by empty circles identified by numbers and speakers are represented by filled circles identified by letters� The association lines between nodes represent how reliably a contrast produced by a given speaker is perceived by a given listener� Thick lines indicate that the intended categories produced by the speakers are frequently perceived correctly by the listener; thin lines indicate that this is rarely the case� The top panel illustrates a situation in which some speakers (filled circles) are overall more intelligible and some listeners (empty circles) are overall more reliable, as indicated by the number of thick lines departing from each node� Crucially, the two phenomena are independent� Speaker A's productions are reliably perceived by all listeners, whereas listener 3 reliably perceives productions from all speakers� Using the blood types metaphor introduced above, speaker A would thus be an example of a "universal donor" and listener 3 would be a "universal recipient"� The mid panel depicts a link between production and perception within individuals� This is akin to the results reported by  Perkell et al� (2004a,b) , in which subjects participated in both a production and a perception task� The mid panel thus features three tiers, since subjects (in the central tier) serve as both listeners and speakers (hence the juxtaposed filled and empty circles identified by Greek letters), and thus both listeners (top tier) and speakers (bottom tier) are required� The illustration shows that some individuals (i� e� node β) are both accurate in their productions (thick lines connecting to listeners in the top tier) and reliable in their perceptual judgements (thick lines connecting to speakers in the bottom tier)� Using the blood types metaphor introduced above, the individual β would thus be an example of an individual who is at the same time a "universal donor" and a "universal recipient"� The bottom panel illustrates the presence of an interaction between speaker-and listener-specific behaviour� Some speakers might still be overall more intelligible than others, and the same might apply for listeners� Crucially, however, there is no such thing as a "universally intelligible speaker" or a "universally proficient listener", as in the independence scenario, and thus (a fortiori) no individual who is both, as in the link scenario� Rather, a listener might perceive more reliably the contrasts produced by a given speaker, whose productions are in turn perceived less reliably by a different listener� Similarly, a given listener might be very reliable at decoding productions from a particular speaker, but perform very badly on productions from a different speaker� This is exemplified by speaker A being badly perceived by listener 1, who however is very reliable at decoding contrasts produced by speaker C� This is still compatible with some individual being overall better listeners (e� g� listener 3, with two thick lines departing from its node) or worse speakers (e� g� speaker B, with no thick lines departing from its node), as in the independence and link scenarios� However, in the interaction scenario these main effects can be modulated by specific interactions, and thus neither accuracy in production nor precision in perception need to be understood in absolute terms� In the following sections, we explore the hypothesis of an interaction between speaker-and listener-specific strategies, using a dataset on the production and perception of focus in German collected for various purposes (Mücke and Grice, 2014, focussing on production; Grice et al�, ms�, focussing on perception)� Before providing an analysis of the interaction between specific speaker and listener behaviours (3�3�), we thus summarise some of the relevant aspects of the two original studies�.