A DBMS (Database Management System) developer designs, implements, manages, and maintains database structures. They work on various tasks like data modeling, normalization, creating ER diagrams, and SQL queries optimization. They ensure data consistency, integrity, security, and recovery through backup procedures. They also work on data migration, transformation, and scripting. They troubleshoot and correct database issues, implement rules and procedures for data sharing. They closely work with developers to improve applications and establish best practices. They also monitor system health and performance, and ensure high levels of performance, availability, and security.