During construction, the Procuring Authority carried out intense monitoring of the works. This was a key element in the successful delivery of the works on budget and on time. A joint team comprising representatives of the Procuring Authority and the Project Company was created to supervise the works.

KPIs during the operations phase are also considered one of the key factors for success of the project. The key performance indicators in the PPP contract are called "Quality and Availability Indexes". There are around 15 indexes related to several aspects, like delays, cleanliness, etc. For every index, there is an associated payment deduction. The Payment Per Demand or Availability (PPD) is the amount paid by the Procuring Authority to the Project Company for the quality and availability of the tram's service.

These KPIs are thoroughly monitored by the Procuring Authority, which has four people full time in charge of controlling the quality of service.

Some KPIs associated with delays, for instance, are automatically generated by the software that controls the operation of the trams, which controls all aspects of the service (times of arrivals and departure in all stations, speed, location of the trams, etc.). Other KPIs are monitored via inspections carried out by the Procuring Authority.

KPIs seem to be working for both the Procuring Authority and for the quality of the service. From the Project Company's point of view, this monitoring is perceived to be too strict. However, undoubtedly this high level of monitoring is supporting the excellence in service and maintenance of all assets.