A Practice Note addressing permissive joinder of parties in civil litigation under Federal Rule of Civil Procedure (FRCP) 20. This Note provides basic considerations for counsel under FRCP 20, including the factors courts analyze in determining whether to allow permissive joinder, which parties can seek joinder and which parties can be joined under the rule, permissive joinder after removal, fraudulent joinder and fraudulent misjoinder, when to seek joinder, and appealing orders under FRCP 20.