This paper aims to demonstrate several issues related to mixed business, in regard of Rules of Jurisdiction in Mixed Business, Solidarity in Mixed Business, Interests Due According to Mixed Business, Procedural Rules in Mixed Businesses, Summary Proceedings in Mixed Business, Arbitration Clause in Mixed Business, Rules of Evidence in Mixed Business, Compliance of the Mixed Business’ Evidence to a Dual Legal System as a General Rule, Compliance of Mixed Business’ Evidence to a Unified legal system as an exception. Keywords: Mixed Business, Jurisdiction, Evidence, Solidarity, Interests, Arbitration.