Without global exception handling, Spring returns raw stack traces or inconsistent error shapes. This article shows how to centralize all error handling in one place and return structured, RFC 7807-compliant responses. The Problem Without Global Handling Default Spring Boot error responses are inconsistent: // Validation failure (MethodArgumentNotValidException) { "timestamp": "2026-05-03T10:00:00.000+00:00", "status": 400, "error": "Bad Request", "path": "/api/orders" } // Details of which fields failed? Not included. // Custom exception not handled // → 500 Internal Server Error with a stack trace in the body (in dev mode) What clients actually need: