Mitsui Car Shares, formerly Careco, is a Japanese car-sharing service operated mainly from Mitsui Repark locations in the Tokyo metropolitan area and parts of Kansai, including Osaka and Kyoto. Members can use a vehicle around the clock, with bookings available from 30 minutes, making the service suitable for short errands, day trips and business travel. The stated service price includes fuel and insurance, offering an alternative to owning a car or using conventional rental services.

Customers can join through individual or business plans and reserve cars using the website, member portal or app. The fleet offers a variety of vehicle types, with choices by price, vehicle category and intended use; the service also provides guidance on electric vehicles. Cars are collected and returned at designated stations, with in-car equipment such as fuel cards and cleaning kits. Mitsui Car Shares also offers member benefits, including V Points, usage coupons, travel-related perks and preferential rental-car offers. For businesses, it promotes potential cost savings and improved operational efficiency.