The TIME project: Timing and Sound in Musical Microrhythm (2017–2022) studied microrhythm; that is, how dynamic envelope, timbre, and center frequency, as well as the microtiming of a variety of sounds, affect their perceived rhythmic properties. The project involved theoretical work regarding the basic aspects of microrhythm; experimental studies of microrhythm perception, exploring both stimulus features and the participants’ enculturated expertise; observational studies of how musicians produce particular microrhythms; and ethnographic studies of musicians’ descriptions of microrhythm. Collectively, we show that: (a) altering the microstructure of a sound (“what” the sound is) changes its perceived temporal location (“when” it occurs), (b) there are systematic effects of core acoustic factors (duration, attack) on microrhythmic perception, (c) microrhythmic features in longer and more complex sounds can give rise to different perceptions of the same sound, and (d) musicians are highly aware of microrhythms and have developed vocabularies for describing them. In addition, our results shed light on conflicting results regarding the effect of microtiming on the “grooviness” of a rhythm. Our use of multiple, interdisciplinary methodologies enabled us to uncover the complexity of microrhythm perception and production in both laboratory and real-world musical contexts.