Ensure the agency is transparent about their methods and processes. They should provide clear explanations of their strategies and tactics, as well as regular reports on performance and progress.

Look for an agency that offers customized solutions tailored to your specific business goals, target audience, and industry.

Assess the agency's experience and expertise in SEO. Look for their portfolio, client list, and examples of successful campaigns they've run. An agency with a diverse range of clients and industries may be more versatile.