NetSuite, a prominent ERP system, is pivotal for managing various financial processes such as accounts payable, accounts receivable, and expense management, making it essential for organizations to integrate their internal or customer instances with other applications. The integration with NetSuite's API, whether through SOAP, REST, or suiteQL, facilitates access and interaction with its data and functionalities, though it comes with challenges like complex permissions, unclear error messages, and potential slow response times. Best practices for integration include applying specific filters to requests to avoid timeouts and adding custom error messages for rate limit issues. Practical integration examples include streamlining purchase requisition approvals via Slack, adding financial documents to storage applications like Box, and creating customizable financial dashboards. Merge offers a Unified API to simplify complex integrations with systems like NetSuite, providing features such as normalized Common Models and integration observability to enhance performance and reliability. Integrating with NetSuite not only saves time and reduces errors for internal operations but also boosts customer retention and market growth for customer-facing integrations.