The institution of the powiat vozny (vaznys) established by the Second Statute of Lithuania had developed from the former function of the vizh (vižas) in the courts of selected judges. Following the introduction of the vozny function, vizhes were demoted to the lowest link of court executors employed by state-non-judicial or private estate administrations. The number of voznys in each powiat of the GDL ranged from several to a dozen and more. Any powiat nobleman of impeccable reputation who had immovable property in the area could be sworn in as a vozny. Voznys would serve in both powiat land courts and castle courts. At first they were appointed by the voivode’s discretion, later voivodes would appoint voznys elected at sejmiks, based on the noblemen’s request. Each powiat viozny had a certain territory for his supervision and service. This could have been a volost, a district, etc., though most often the territory assigned to a vozny was indicated as a powiat. The number of voznys was not regulated – there could be several voznys in a volost or a single vozny for several volosts and there was no literacy requirement to become a vozny. Only the vozny general of the powiat introduced by the Third Statute of the GDL was expected to be able to read and write. Kaunas powiat was formed after the administrative reform of the GDL in 1565–1566. It stretched in a strip widening towards the southwest from Kėdainiai (Samogitia) in the north to Vyštytis in the south, was the smallest of all powiats in the Voivodeship of Trakai covering the area of around 6045 km². There is no available information on the appointment of the first voznys in Kaunas powiat. They might have been appointed together with the first composition of the post-reform land courts at the beginning of 1566 as it was the case in Slanim powiat where on 1 June 1565 eight powiat voznys were appointed. Inscriptions made by voznys themselves make up a small part of all the records in these books. It should be noted that as time went by and the work of court offices improved, voznys’ work became more intense though less “noticeable”. As court executors they continued to participate in all stages of the land courts’ activities, yet the clerks responsible for record keeping would incorporate them into both the “notarial” (recording of property-related acts) and the procedural (complaints, inspections, litigations) spheres. The article analyses the work of powiat voznys, based on the oldest preserved books of Kaunas land court (10 books 1566–1601). Numerous examples from manuscript books of Kaunas powiat land court employed in the work (3699 inscriptions on 5824 folios in the analysed books) revealed that powiat voznys were the key technical administrative cog in the institution of the land court. Voznys were important in the notarial block of court books indicated therein as the principal witnesses, executors, and officials responsible for statement preparation. Their role in court cases is often primary and they also participate in the work of the lowest link of powiat courts, namely company (kuopa) courts. Not a single court matter could have been solved without the participation voznys as they were required not only for the inspection of loss, but also for witnessing the authenticity of documents and their copies, etc. Moreover, court books contain a lot of “non-standard” information on voznys, including that describing the difficulties and obstacles they would face in their work, a spark of class-related consciousness as well as their activities as ordinary noblemen who work on personal documents, participate in litigations and arguments, file complaints and protests. The investigation of the activities of Kaunas powiat voznys opens new possibilities for the research of the land court as a noblemen’s institution.