Small molecule imaging: Aurora kinase A (AKA) was imaged in live cells using an in cellulo bioorthogonal two-step reaction with a small molecule and a fluorescent reporter. The small molecule was localized to spindle poles and microtubules during metaphase, consistent with the localization of both endogenous and GFP-/RFP-tagged AKA. Using this approach, changes in AKA distribution during mitosis were also observed.