This paper is an attempt to fathom, using court records, how janissaries as regiments managed to make ends meet in the troublesome late seventeenth century when long wars bloated the number of soldiers and wage arrears were commonplace. Janissaries had to survive not only as individuals but as regiments, not completely giving up their military duties. What types of businesses were the regiments in, and who in a regiment were the main actors? Which regiments came to court more often than others? Did their regimental characteristics affect their economic activities? Janissaries in this period are mentioned in court records as members of their regiments more often than before, which seems to indicate that the regiment was becoming the center not only of their military activities but also economic. There were many janissary regimental waqfs that avidly acquired real estates, including those of the prominent regiments that were given special positions in processions. These waqfs were managed by mütevellis who were often also their odabaşıs, “junior officers” of the regiments. The visibility of odabaşıs as the key person of the regimental activities is noteworthy, and it seems that an odabaşı was often practically the head of his regiment. While focusing on the regimental waqfs in the main, this paper will also pursue the traces of other businesses that the regiments were unofficially and illicitly in. They must have been something that did not require too much time or refined technique and could be done with the help of the physical force of their manpower, such as transporting grains, firewood, dealing in coffee, or kidnapping free men and women to make them slaves. There are many clues in court records, which are underused largely because we tend to prejudge janissaries as irrelevant and external to the civilian activities done in court. Court records should be used all the more because new empirical studies of archival documents by Gülay Yılmaz and Abdülkasım Gül provide the big picture. This paper will base itself on published and unpublished court records of Istanbul main court (defters 9, 10, 11, 12, 18, 19, 20, 21, 22, 23) and Istanbul Bab court (defters 3, 46, 54) together with Mühimme defters, Atik Şikâyet defters, and occasional chronicles of the same period.