delovanje

1. activity; action
   Njegovo političko delovanje trajalo je dvadeset godina. — His political activity lasted twenty years.
   Potrebno je hitno delovanje države. — Urgent action by the state is needed.
2. (of a drug, substance) effect; action
   Delovanje leka počinje posle pola sata. — The drug takes effect after half an hour.
   Ispitivali su delovanje zračenja na biljke. — They studied the effect of radiation on plants.

In the sense 'effect' it usually takes na + acc.: delovanje na organizam.