Estonian military intelligence and counterintelligence agencies were established at the start of the Estonian War of Independence. The Information Gathering Department (Teadete Kogumise Osakond) worked under the command the General Staff and was assigned to perform both intelligence and counterintelligence tasks. The IGD had up to 10 Information Gathering Stations (IGS). Mobile stations were under the operational command of the 1st, 2nd, and 3rd Divisions. There were also stations in Tartu, Kuressaare, Narva, Pärnu, Petseri, Võru and Viljandi (the last of these was most likely disbanded before the end of war). The IGD relied mostly on its network of agents.

In 1919, agents were paid a monthly salary of between 300 and 475 Estonian marks. Agents who crossed the front line into Russia were paid extra amounts for additional expenses. The yearly IGS expenditures of the 1st Division were 153,500 Estonian marks, which included the salaries of its officials and agents plus extraordinary expenses, such as trips to Russia. This can be compared with the costs of salaries and daily allowances for the 1st Division. The Finance Department of the Estonian Army’s Supply Administration allocated the required money to the 1st Division for the IGS. Statements of expenditures were submitted later along with payroll lists.

A total of 52 agents are known to have served in the 1st Division’s IGS during the War of Independence. Yet there were never more than 20 agents on the payroll at any given time. There were up to five officials on the IGS payroll and eight different persons working as officials over the entire course of the war. Turnover was high among IGS personnel and only five agents were on the payroll from start to end. The commander of the 2nd Division requested an increase in the number of agents in his division to 25 in total. Overall, it is difficult to assess how many agents there were in Estonian military intelligence as a whole.

The agency drew up surveillance reports on the internal situation in Estonia. Information on enemy agents and supporters of the Bolsheviks was gathered through surveillance. The agency countered Bolshevik efforts to undermine the war effort of the Republic of Estonia, which consisted of agitation, spreading rumours, and distributing leaflets. Suspects were sent to courts-martial based on evidence gathered by agents. Estonian agents gathered military intelligence and information on the moods of the population in Russia by crossing the front line. Such information could be used to create propaganda slogans. At least one plan is known of for distributing Estonian leaflets in Petrograd using Estonian agents.

Various such activities continued in the latter half of the war, but an additional confrontation emerged between Estonia and the Russian White Army. It has previously been believed that rumours spread by Bolshevik agents exacerbated tensions in relations between the Estonian military leadership and the Russian White Army. New sources clearly indicate that Estonian agents operating in Russia noticed that the attitudes of the Russian White Army regarding Estonia were increasingly negative. It can be considered a success that Estonian intelligence agents verified the names of more than fifty officials and agents of the Russian North-western Army.