Paratransit or Intermediate Public Transport, is a type of transportation services that supplement fixed-route mass transit by providing individualized rides without fixed routes or timetables. Paratransit services may vary considerably on the degree of flexibility they provide their customers. At their simplest they may consist of a taxi or small bus that will run along a more or less defined route and then stop to pick up or discharge passengers on request. At the other end of the spectrum—fully demand responsive transport—the most flexible paratransit systems offer on-demand call-up door-to-door service from any origin to any destination in a service area. In addition to public transit agencies, paratransit services may be operated by community groups or not-for-profit organizations, and for-profit private companies or operators.

Demand-responsive transport (DRT), also known as demand-responsive transit, demand-responsive service, Dial-a-Ride transit, flexible transport services, Microtransit, Non-Emergency Medical Transport (NEMT), Carpool or On-demand bus service is a form of shared private or quasi-public transport for groups traveling where vehicles alter their routes each journey based on particular transport demand without using a fixed route or timetabled journeys. These vehicles typically pick-up and drop-off passengers in locations according to passengers needs and can include taxis, buses or other vehicles. Passengers can typically summon the service with a mobile phone app or by telephone; telephone is particularly relevant to older users who may not be conversant with technology.