An ocean observatory—Consisting of a realtime, cabled system in the Sea of Oman and an internallyrecording, autonomous mooring system upgraded in 2010 to a cabled system in the northern Arabian Sea—was installed in 2005. Lighthouse R & D Enterprises designed and installed and now operates and maintains the systems with permission from the Oman Ministry of Agriculture and Fisheries Wealth. The two systems have collected a continuous sevenyear time series record of current velocities, temperature, pressure, salinity, dissolved oxygen, and turbidity in a region where several water masses converge and subsequently spread southward to the Indian Ocean. The systems have provided new insights into physical and biological oceanographic processes of the northwestern Indian Ocean, which is strongly affected by monsoonal winds, along with lessons learned and best practices in the operation and application of ocean observatories to ocean science. In this presentation, we show four recent studies on the scientific highlights resulting from the data collected by the two systems with supporting data from other sources. The topics of those four studies include: ①The deepwater oceanic responses excited by the passage of Cyclone Gonu, the largestever recorded cyclone in the region; ② The seasonality associated with the upwelling of low oxygen water along the northern Oman coast and insights on the interannual variability of this process; ③ The temporal and spatial evolution of an acoustic backscatter layer; ④ The pulselike salinity/temperature events in the northeastern Arabian Sea and Sea of Oman. The observatory provides a longterm, timeseries data record useful for performing important scientific research related ot the general dynamical patterns of the region, quantifying seasonal variability of water column properties, and establishing a time series of sufficient duration to deduce the potential impacts of climate change. Furthermore, observations taken over the full, 25+ year lifetime of a typical cabled system will be extremely useful for evaluating numerical ocean circulation and coupled atmosphericoceanic models under various climate scenarios.