STSI d.o.o. as a holder of certificate ISO 9001, OHSAS 18001, ISO 14001 continually strives to operate at the highest possible level of quality. Therefore, we are implementing into our business a pre-qualification procedure of the present and potential suppliers. Suppliers who are not pre-qualified or not meeting the pre-qualification criteria will not be able to participate in tenders advertised by STSI d.o.o.. Please complete the pre-qualification questionnaire, which can be downloaded here and send it to the address firstname.lastname@example.org. The results of the pre-qualification will be notified and for any additional questions regarding pre-qualification you can contact us on mentioned e-mail address.