Coherent technologies offer promising solutions for high-speed optical access beyond the rate of 100 Gb/s. By embracing coherent detection, optical access system capacity can be enhanced by encoding information in amplitude, phase, as well as polarization components of a carrier. With the use of digital signal processing (DSP), coherent receivers can mitigate signal impairments through the use of distortion equalization and fiber dispersion compensation. Compared to Intensity Modulation / Direct Detection (IMDD), coherent detection excels in chromatic dispersion (CD) equalization, enabling the utilization of C-band wavelengths, achieving a higher access link budget. On the other hand, system complexity is one of the challenges of integrating coherence technologies into optical access systems. There are ongoing efforts focused on streamlining coherent systems to meet the optical access requirements of cost and complexity reduction. This month’s issue of CTN offers a comprehensive revi