An IBM Cognos developer designs, develops, and implements business intelligence solutions using IBM Cognos Analytics. Their responsibilities include creating data models, generating reports, and developing dashboards for business users. They also maintain and troubleshoot existing Cognos applications, ensuring optimal performance and data accuracy. They work closely with business analysts and stakeholders to understand the business requirements and translate them into technical specifications. They also use their knowledge of SQL and relational database concepts to manipulate and retrieve data. Furthermore, they may provide training and support to users, enhancing their understanding and efficient use of the Cognos system.