Bangkok · Sukhumvit
Along the Sukhumvit Line

The Sukhumvit corridor follows the BTS Sukhumvit Line as it runs east from Asok through Thonglor, Ekkamai, Phra Khanong and On Nut, and then on toward Bang Na. A large share of the city's condominium stock sits within a short walk of those stations. That is the point of living here, and also the reason the area feels crowded.
Sukhumvit Road itself is often slow. People who live here and work along the same line tend to use the train for most trips and treat the road as a last resort. Sois (the side streets numbered off Sukhumvit) vary widely: some are quiet residential lanes, others are packed with restaurants and bars. Thonglor and Ekkamai stay busy late. Further east, On Nut and Phra Khanong are more mixed and, in many buildings, a little calmer at night.
Asok is a transfer point. The BTS and the MRT Blue Line meet there, which makes it useful if you work toward Rama 9, Huai Khwang or Silom. It is also loud, and several large malls sit on top of the junction. If you want the transfer but not the noise, look one or two stops east or west and walk or take a short hop to the interchange.
Before you sign a lease, walk the route to the station at the hour you will actually travel, including the last stretch through the soi. Check whether the building has a useful way out to the platform or whether you will be walking along a main road without shade. Visitor parking is tight in many buildings along this strip.
If your days will be spent further east, or at a school campus in that direction, skip ahead to Bang Na and the east rather than assuming a Thonglor address will make the school run simple.