This chapter investigates recent research-driven developments in wavelength dispersive X-ray fluorescence (WDXRF) and energy dispersive X-ray fluorescence (EDXRF), focusing on instrumentation, analytical performance, and emerging applications. In WDXRF, the study critically examines the evolution of detector systems including proportional counters and scintillation detectors alongside advancements in geometrical configurations such as tube-above setups, crystal technologies, improved signal-to-noise ratios, and advanced data processing algorithms, which collectively contribute to higher resolution and precision in multi-element analysis. The chapter also explores recent trends in detector architecture and system automation that are shaping the next generation of WDXRF instruments. In the context of EDXRF, this work evaluates ongoing innovations in compact and high-throughput systems, with particular focus on cutting-edge modalities such as total reflection XRF (TXRF), grazing emission XRF (GEXRF), and micro-XRF (µ-XRF). These techniques demonstrate extended analytical capabilities for trace, ultra-trace, and spatially resolved elemental analysis in complex matrices. This chapter provides a foundation for researchers seeking to understand the instrumental evolution of XRF and its implications for future analytical research and industrial integration.