Broadcasters
* Radiodiffusion Television Ivoirienne, state broadcaster of Ivory Coast * Radio Taiwan International, a radio station in Taiwan * Reti Televisive Italiane, an Italian broadcaster and subsidiary of MediasetOther businesses
* RTI International, formerly Research Triangle Institute, a not-for-profit American research organization * RTI International Metals, an American company producing titanium * RTI Producciones, a Colombian television production companyIn science and technology
In computing and telecommunications
* Run-time infrastructure (simulation)In medicine
* Reproductive tract infection * Respiratory tract infection * Reverse-transcriptase inhibitor, a class of antiretroviral drugOther uses in science and technology
* Ramp travel index, a measure of an off road vehicle articulation, ability to keep all wheels in contact with the ground over uneven terrain * Rayleigh–Taylor instability, an instability of an interface between two fluids of different densities which occurs when the lighter fluid is pushing the heavier fluid * referred-to-input *Other uses
* Response to intervention, in education * Right to Information Act, 2005, India * Rti (Lučani), a village in Serbia * Resistance to interrogation, a technique taught to soldiers {{disambiguation