In　the　field　of　special　distillation　processes,　pressure-swing　distillation　(PSD)　is　the　one　able　to　be　utilized　to　separate　a　mixture　with　close　boiling　point　or　forming　azeotrope.　The　PSD　separation　is　based　on　the　fact　that　a　mixture　of　components　displays　sensitivity　to　pressure,　which　means　that　a　simple　change　in　pressure　can　alter　the　relative　volatilities　of　the　components　of　the　mixture　with　close　boiling　points　or　forming　azeotrope.　Remarkably,　PSD　can　achieve　pure　products　without　introducing　new　additives　compared　with　extractive　distillation　and　azeotropic　distillation.　Thus,　PSD　is　an　environmentally　friendly　process.　This　chapter　presents　a　wide　aspect　of　PSD　in　operation　principle,　operation　mode,　conceptual　design,　and　a　brief　comparison　among　different　special　distillation　processes.　©　2022　Elsevier　B.V.