These materials deal with the fixation and modification of working conditions as well as the managerial prerogatives of the employer and its limits, and are intended to be students’ materials for preparing the lessons. Throughout these lessons it is possible to guess the influence of the flexicurity policy -much more flexibility than security- in the ruling of the different institutions regarding contract of employment. Besides the flexibility in the recruitment -contracts of employment, temporary agency work, outsourcing- which is not object of these materials, the impact of flexibility on the determination and variation of the most relevant working conditions -functions, salary, working time, place of work- and the increase of employer’s power before the employees can be detected in all topics studied. Nevertheless, it is also possible to appreciate the relevance of information and consultation to workers’ representatives due to the European legislation. These materials try to be more than a simple enumeration of the rules -what the law says-, but they also make reference to the political ideologies to which these rules come from. Employment law is aimed to solve the conflict of interests between employer and employee, imposing some limits to the employers’ preeminent position when establishing working conditions, but also protecting companies’ productivity and efficiency. Hence, the need to decide what is prevalent in any case becomes crucial.