Sousveillance ( /suːˈveɪləns/ soo-VAY-ləns; French pronunciation: [suvɛjɑ̃s]) refers to the recording of an activity by a participant in the activity typically by way of small wearable or portable personal technologies.

Sousveillance has also been described as "inverse surveillance", i.e. from the word surveillance which is formed from "sur" (French for "from above") and "veiller" (French for "to watch"), by changing "sur" to "sous" (French for "from below").

While surveillance and sousveillance both generally refer to visual monitoring (i.e. "veiller" being "to watch"), the terms also denote other forms of monitoring such as audio surveillance or sousveillance. In the audio sense (e.g. recording of phone conversations) sousveillance is referred to as "one party consent".

Inverse surveillance is a subset of sousveillance with a particular emphasis on the "watchful vigilance from underneath" and a form of surveillance inquiry or legal protection involving the recording, monitoring, study, or analysis of surveillance systems, proponents of surveillance, and possibly also recordings of authority figures and their actions. Inverse surveillance is typically an activity undertaken by those who are generally the subject of surveillance, and may thus be thought of as a form of ethnography or ethnomethodology study (i.e. an analysis of the surveilled from the perspective of a participant in a society under surveillance).