Bicing is a bicycle-sharing system in the city of Barcelona, Catalonia, Spain, which was implemented in March 2007, promoted by the City Council. The municipal company Barcelona de Serveis Municipals (B:SM) is the manager of the service, while the exploitation concession corresponds to Pedalem Barcelona since 2019, a Temporary Union of Companies formed by CESPA (Ferrovial Services) and PBSC. Between 2007 and 2018, Clear Channel was the company in charge of this task. It is similar to the Vélo'v service in Lyon or Vélib' in Paris, and uses the same bicycles and stations as used in Stockholm, Oslo, and Zaragoza. Its purpose is to cover small and medium daily routes within the city in a climate-friendly way, eliminating the pollution, roadway noise, and traffic congestion that motor vehicles create.

As of 2021, the city council and Pedalem Barcelona manage and maintain the bike share system, provided by PBSC Urban Solutions, an international bike share company that provides bikes and stations. To use it, users must acquire a yearly membership. Currently the network consists of more than 519 stations to lend and return over 7000 bicycles distributed throughout the system.

The stations are situated through most of the flat areas of the city with a distance of around 300 to 400 metres between each one. Many are situated next to public transport stops to allow for intermodal use. Metro stations usually have signs pointing to the locations of nearest Bicing stations. The bikes can be borrowed from and returned to any station in the system, making it suitable for one-way travel. Each station has between 15 and 30 parking slots to hold and lock bicycles, but in highly transited areas many stations may be close together.

To take out a bike, users simply swipe the contactless RFID card at a docking station to identify themeselves in the system, which then unlocks a bike from the support frame. Bicycles can be used for the first 30 minutes at no extra cost, with subsequent half-hour blocks (up to 2 hours) costing 0.70 € each. Use of a bicycle for more than 2 hours at a time is discouraged with a penalty rate of 4.20 € per hour, but also with the possibility of having membership cancelled after a certain number of uses in excess of two hours. To return a bicycle, users simply place the bike in a spare slot at a Bicing station; the bike is recognised automatically and is locked into place.

Specialised vans are used to redistribute Bicing bicycles between the stations to even out usage patterns. However, as of November 2007, the number and frequency of vans is not able to keep up during the peak hours, making it very difficult to find a spot at which to return the bike in some areas.^{[citation needed]}

Use of the system is based on membership, and users can subscribe online or by visiting a service office. Bicing member cards are only sent to addresses in Catalonia in an attempt to prevent tourists from using the system. This limitation was imposed upon the city council by pre-existing local bike hire companies (grouped under Bicitours) that feared what they called illicit competition from the Bicing system. Bicitours and the city council agreed to enforce a block of ten minutes to change bikes (that is, when docking a bike, the user is prevented from leaving with another bike for ten minutes). As a result, tourists are barred from using what is officially denominated a "public transport system".

The bike is specially designed to prevent theft of parts, or of the whole bike, as well as to prevent vandalism. It is also designed to be easily recognised. However, common user complaints include missing bells, cut brakes, and poor maintenance. Bikes have sometimes been stolen, even by sawing the anchors that fix bikes on the stands, and found repainted.^{[citation needed]}

Bike stations have generally replaced on-street car or motorcycle parking spaces, though others were placed in large pedestrian areas. Each station includes a long series of docks for bikes, with a computerized pylon at one end for completing transactions.