As a concept, the psychological contract will evolve and change, both in its implications and in its definitions. A healthy psychological contract is a contract in which both parties agree that there is a proper balance between donation and taking. This is impossible to achieve where there are many hidden perceptions, so the first goal is to increase openness and mutual awareness. Faced with increased awareness, most people tend to make compromises and work agreements more positive. It is said that an iceberg is hidden under water at 90%. This metaphor fits very well into the psychological contract in which most perceptions of the contract are unwritten and hidden, in accordance with their definition. Descriptions and definitions of the psychological contract first appeared in the 1960s, particularly in the work of organizational and behavioral theorists Chris Argyris and Edgar Schein. Since then, many other experts have presented ideas on this subject and continue to do so, either by focusing specifically on the psychological contract or by addressing it from a particular point of view, which are numerous. The psychological contract is a profound and varied concept and open to a wide range of interpretations and theoretical studies. The term «psychological contract» refers to the expectations, beliefs, ambitions and duties of the individual, as perceived by the employer and the employee.
The concept was born in the early 1960s and is at the heart of understanding the working relationship. Based on the lessons learned from psychology and organizational behaviour, attention to the «human» side of the employment relationship provides employers with a strong justification. Although the concept of psychological contract describes the expectations of both employers and workers, the concept has been studied primarily from the employee`s perspective. You will see many different definitions of the psychological contract. It is a complex concept when it is considered beyond its most fundamental principle, and it is dynamic when viewed in every situation: it is not fixed or static – it contains forces and feelings that can fluctuate and be quite chaotic. Psychological contracts are defined by the relationship between an employer and a worker, where there are unwritten reciprocal expectations for each party. A psychological contract is more defined than a philosophy, not as a formula or a developed plan. Characterization of a psychological contract by qualities such as respect, compassion, objectivity and trust.  Psychological contracts are formed by beliefs about exchange agreements and can occur in many situations that are not necessary employer-worker.  It is, however, of the utmost importance in its function of defining the employment relationship between the employer and the worker. As such, the psychological contract is an essential but implicit agreement that defines employer-employee relations.