Interwell interference is a ubiquitous concern in shale reservoir development that results in declines in productivity. It mainly appears when a high number of closely spaced parent/offset and child/infill wells are placed in the shale producing zone to stimulate hydrocarbon production. Its consequences become risky when multi-branch horizontal infill wells are employed through massive (and multi-stage) hydraulic fracturing. This review aims to give a comprehensive and applied insight into interwell interference in shale reservoirs. It starts with the root causes and contributing factors, followed by a discussion of various forms of well-interference. Furthermore, different monitoring methods along with detection strategies are highlighted. Numerical approaches have also been explained to understand the fluid flow and geomechanics involved in the interwell interference. Later on, various mitigation techniques are highlighted. Finally, suggestions for future research needs to address the current challenges are discussed. © 2023