How much acclimatization is recommended prior to the start of the expedition?

There will be no situation where we will encounter a need for acclimatization. The maximum elevation gain is 3000m in 12 hours. The change in temperature from the main cities to the trekking areas is not too severe. Sometimes in Sapa the temperature can drop 15 degrees from Hanoi but that caneasily manages with proper preparation and layered clothing. The most difficult things to overcome when you get to Vietnam may be jet lag and culture shock. Taking it easy on the first day and a Opentour guide will help you overcome those problems.