A Checklist of issues that defense counsel should consider when responding to a state or federal complaint asserting a Massachusetts common law breach of contract claim. Specifically, this Checklist provides guidance on asserting defenses, counterclaims, crossclaims, and third-party claims. This Checklist also highlights alternative claims, such as violations of the Massachusetts Consumer Protection Act (Massachusetts General Laws Chapter 93A), promissory estoppel, and tortious interference and offers considerations for challenging remedies and taking advantage of certain defensive procedures.