In response to the increasing demand for water reuse to bolster water security, attention is shifting towards achieving not only a substantial volume but also high-quality recovered water. Membrane-based water treatment processes, especially reverse osmosis (RO), have gained widespread adoption in the water-reuse market due to their efficient removal of particulate matter, bacteria, viruses, and dissolved solids with an efficiency exceeding 99%. While RO ensures water quality, system recovery is often constrained by low water flux in RO membranes, a consequence of the tradeoff between water permeability and salt permeability. Although multi-stage RO can enhance recovery to over 85%, it complicates membrane design and raises application costs. Moreover, high-recovery operation frequently leads to membrane fouling. To address these challenges, circle-sequence reverse osmosis (CSRO) has been developed as a modified configuration of semi-batch closed-loop RO to increase system recovery rate with a simplified design and reduce fouling propensity through staged design and flow reversal operation. CSRO allows to achieve a high recovery as well as to inhibit mineral scaling and organic fouling. This study introduces the concept of novel CSRO and evaluates its performance during pilot operation. Initially, achievable recovery was examined using discharged water with a total dissolved solids concentration of approximately...