Short-range order (SRO) has been proposed in various alloys including complex concentrated alloys (CCAs), Fe-, Ti-, Cu-, Al-, Mg- based alloys, etc. However, beneficial utilization of SROs in the design of new alloys has been difficult, due to the lack of fundamental understanding of SRO as well as the absence of direct microscopic proof. The classical understanding of SRO, i.e., detrimental planar slip induced by SROs, does not do full justice to the complexity of this problem, as can be seen in recently developed CCAs and lightweight steels with unexpected improvements in mechanical properties while having planar slip mechanisms. Here, we aim to understand the dominant factors for SRO characteristics and the fundamentals of SRO-assisted deformation micromechanics directly observed by the RevSTEM technique, focusing on the SFE-SRO interactions in CCAs. This study will provide the guidelines for how to fabricate and manipulate the characteristics of SRO in alloys of interest.