A Sirdar is a Sherpa mountain guide who manages all the other Sherpas in a climbing expedition or trekking group. The Sirdar is typically the most experienced guide and can usually speak English fluently. The Sirdar's responsibilities include:

• assigning responsibilities to the other guides
• hiring and paying local porters
• purchasing local food during the trek/expedition
• making the final decision regarding route choices
• handling other trip logistics such as dealing with government officials or police.

The normal progression to Sirdar usually involves starting as a porter, working their way up to being a kitchen assistant, on to an assistant guide and then finally to Sirdar. Sirdars do not normally carry loads but will do so on occasion such as carrying the pack of a client who is having difficulties from altitude sickness.

Sirdar was also a rank assigned to the British Commander-in-Chief of the 19th Century Egyptian Army. The Sirdar resided at Sirdaria, a three block long property in Zamalek which was the home of British military intelligence in Egypt.