Interferometry of variable targets With the current capabilities of optical interferometry array, tackling the variability of the sources is a challenge. A characteristic of hot stars winds and close environment is their intrinsic variability, revealed remarkably by intensive spectroscopic monitoring campaigns. Binarity is also an important source of variability, that has to be managed since many sources with circumstellar material are discovered to reside in such systems. Last but not least, explosive events are not rare, and require to be monitored a dedicated strategy of observation. The different scales of variations for various spectral types will be reviewed, and the adaptation of the interferometric observations discussed. Finally, the advent of interesting imaging capabilities in a near-future will be discussed.