Previous research has established that skilled joint action partners use predictive models to achieve temporalcoordination, for instance, when playing a music duet. But how do joint action partners with different skill levelsachieve coordination? Can experts predict the suboptimal timing of novices? What kind of information allowsthem to predict novices’timing? To address these questions, we asked skilled pianists to perform duets withpiano novices. We varied whether, prior to performing duets, experts were familiar with novices’performancesof their individual parts of the duets and whether experts had access to the musical scores including the novices’part of the duet. Familiarity with the score led to better coordination when the score implied a difficult passage.Familiarity with novices’performances led to better joint action coordination for the remaining parts of the duet.Together, the results indicate that experts are surprisinglyflexible in predicting novices’suboptimal timing.