In recent years, latent hybrid threats have started to urgently challenge the resilience of homeland security in Europe. Among others, these threats include cyber-attacks, organized crime, covert operations, border and maritime disputes, harming critical infrastructure, influence operations, disinformation campaigns, espionage, instrumentalization of migration, the radicalization of various interest groups, terrorism, sabotage, political blackmail, money-laundering, resource scarcity, exploitation of energy dependence, trade wars, and economic rivalry. This chapter will examine how these threats and challenges align with potential countermeasures and responses that should be considered and implemented. In other words, the urgent task for national authorities is to be prepared to respond to the potential destabilization that may come with hybrid attacks. The authors suggest policy recommendations to address hybrid threats to Estonian national security, particularly after Russia's large-scale aggression against Ukraine on 24 February 2022.