Hiring an Acceptance Test Driven Development (ATDD) developer can significantly boost the efficiency and productivity of a software development project. ATDD developers are adept at defining acceptance criteria and tests before the development process begins, which helps ensure that the final product meets the business requirements accurately.

One major advantage is enhanced communication. ATDD developers facilitate better collaboration between developers, testers, and business stakeholders, fostering a shared understanding of the project goals. This approach minimizes the risk of any miscommunication or misunderstanding which often leads to project delays or increased costs.

ATDD developers also help improve the quality of the software. By defining acceptance tests upfront, they ensure that the software is built right from the start, reducing the chances of bugs or errors. This proactive approach to testing minimizes the time and resources spent on fixing defects later in the process.

Another advantage is increased customer satisfaction. Since the development is aligned with the customer's requirements from the beginning, the final product is more likely to meet or even exceed customer expectations.

Finally, ATDD developers contribute to shorter development cycles. The clear definition of requirements and tests at the outset makes the development process more streamlined, enabling faster delivery of high-quality software.