Key Takeaway: Joint Russian-Belarusian military exercises in March 2021 demonstrated several new Russian capabilities that could support a permanent Russian force presence in Belarus. Russia’s efforts to cement control of Belarusian forces and permanently deploy forces to Belarus increase Russia’s capacity to threaten NATO’s eastern flank. Russia and Belarus announced plans to open three permanent combined combat training centers in Russia and Belarus. The Kremlin is likely increasing Belarus’ military readiness and integration with Russian forces, augmenting the Kremlin’s capability to mobilize more units for longer durations and increasing Russia’s total force projection capability against NATO. Russian military pilots may begin operating out of Belarusian airbases in 2021. The Kremlin additionally used March 2021 exercises to prepare for Russia’s upcoming annual capstone strategic readiness exercise, Zapad 2021, in September, during which Russian units will likely deploy to Belarus on a significantly larger scale than ever before.