Ensure proper memory ordering in concurrent code by using appropriate memory barriers and atomic operations based on the access pattern. When implementing release-store semantics, place the store fence before the actual store to prevent instruction reordering: ```java // INCORRECT - barrier after store value.store(newValue); storeFence(); // Too late! // CORRECT - barrier before store storeFence(); // Prevents reordering of previous stores value.store(newValue); ``` Key guidelines: - Use volatile for single-writer scenarios requiring visibility - For performance-critical paths with single-threaded access, prefer lazySet() over volatile writes - When implementing custom concurrent data structures, consider using unpadded variants for better memory efficiency - Place state updates before notification in producer-consumer patterns to ensure proper visibility This approach prevents subtle race conditions while maintaining performance in concurrent systems.