järjestävissä
The Finnish word "järjestävissä" is a grammatical form of the verb "järjestää," which means "to organize" or "to arrange." Specifically, "järjestävissä" is the inessive plural form of the present active participle of "järjestää." This means it translates to something like "in the organizing" or "among those organizing." It describes a state or action of being involved in the process of organizing something.
For example, if someone is part of a committee planning an event, they might be described as