I am a tour manager from India and took many groups around the world. Now I am planning to take a group of 15 Indian tourists to Serbia. I am in the process of booking our tour through a local travel agency in Serbia. Is it OK for my group to travel without a visa? Will there be any problem at airport immigration? If yes then what should I prepare so my group can go easily?
At the Serbian Ministry of Foreign Affairs, you can see that Indian citizens with ordinary passports can enter visa-free for up to 30 days in one year.
If the visit you're planning is 30 days or shorter, and nobody in the group has recent trips to Serbia that would cause them to go over the limit, then the answer to your question is yes, it is okay to travel without a visa.
If the visit will be longer than 30 days, or for anyone will exceed the 30-day limit, you can read about the visa application process at http://www.mfa.gov.rs/en/consular-affairs/entry-serbia/visa-requirements.