All of these issues need to be addressed in order to create a satisfactory solution for personnel and management of the organization. For the Crew member in a seniority based system schedules are decided largely on workplace seniority. Those at the top of a seniority list are allowed some choices. As assignments are made and the remaining roster of personnel becomes fewer, managements' systems start to assign the remaining trips based on a weighting of the 4 previously mentioned variables, without any input from personnel.<br>
This does not allow the personnel to have any choice or voice in the schedules they receive. This lack of scheduling awareness until the end of each scheduling period is a major workforce issue and an employee [http://www.time.com/time/business/article/0,8599,1997688,00.html morale problem], often creating a tenuous situation especially where a collective bargaining agreement is in place, and particularly at negotiation time. To address this issue, and to satisfy the growing voice of personnel to have a say in their schedules, in the 1970s the company SBS International, led by Mr. Christian Boegner, created the concept of a Preferential Bidding System (PBS).
This was a new method of allowing personnel to create input data that factored in the calculations of the schedules, while still allowing management a level of control over critical business decisions. This has become a standard in the industry. The newest approach to PBS and crew scheduling takes advantage of the interaction possible via the web, which wasn't possible in the 1970s.<ref>http://www.crewingsolutions.com/sites/all/files/resources/SP-WhitePaperPBS.pdf</ref>
== Real Time ==
Crew members and management can interact with schedules and data in a real-time web interface. Status can be seen and acted upon as it develops and changes, rather than requesting or bidding for a schedule once, then waiting to see the outcome. Although that advance itself was revolutionary at the time [[Preferential bidding system|Mr. Boegner developed the mathematical algorithm to do so]], interactive live PBS crew scheduling is the next step. The internet and its reach are starting to change crew scheduling within the large, global organizations that use it.<ref>http://www.carmensystems.com/research_development/articles/crtr0303.pdf "Solving the World's Largest Crew Scheduling Problem"</ref>
