i. ability to retain certain suppliers operating in the maintenance and construction of rolling stock ii. performance of complex projects that require substantial financial resources and a structured organisational and project management structure iii. interruptions/issues due to system and technology faults, serious natural events and vandalism iv. saturation of high commercial value routes v. alleged potential violations of occupational safety regulations i. structured supplier qualification procedures that include financial assessments as well as technical evaluations ii. management and control procedures to constantly monitor physical and financial performance of infrastructural projects iii. avant-garde security, control and monitoring systems and the creation of specific network maintenance cycles, adopting procedures for the management of irregularities and emergencies with a constant focus on public information and the provision of accessory services to customers iv.