Where defenses usually come from
Many defenses come straight from the contract's language, for example an obligation that was conditional or a limitation of liability that caps what can be recovered. Others come from how the parties behaved, such as the other side failing to perform first or later agreeing to different terms. Some come from the law itself, including filing deadlines and requirements that certain agreements be in writing. The plaintiff's damages are also open to challenge, especially when the plaintiff did little to reduce its own losses. Which of these apply depends on the facts, and timing matters, because some defenses can be lost if they are not raised in the answer.
Records for your side of the story
Gather the signed contract and every draft you exchanged, purchase orders, change orders, and the full email and message history about performance and payment. Records showing what you delivered and when, along with any complaints you raised to the other side, are often central. Look for notices the other side sent, or failed to send, under the contract. Keep everything as it is and suspend routine deletion of related messages. Do not contact the plaintiff to discuss the case without first talking to us, since those messages can become evidence.
Answer, counterclaim, or resolve
The response deadline after service is often short, and a default judgment can follow if it is missed. In a first meeting we check that deadline, whether a forum clause sends the case to arbitration or another court, and whether insurance or an indemnity from a third party might cover the claim. We also consider whether you have claims of your own, such as unpaid invoices, that may need to be raised as counterclaims. Breach of contract defense is usually a mix of litigating and negotiating, and an early view of both sides' exposure helps decide which to emphasize.