There are several synonyms for the phrase "form a business relationship." Some common alternatives include "establish a partnership," "forge a collaboration," "create a strategic alliance," and "develop a professional connection." These phrases suggest a level of intentionality and purpose that is absent from simply "doing business together." They also connote a sense of mutual benefit and shared goals. Other options might include "build a rapport," "cultivate a working relationship," or "network for potential clients." Ultimately, the specific phrase used will depend on the context and the desired tone of the communication. However, these synonyms offer a range of options to help convey the idea of forming a meaningful and profitable business relationship.