The project acomplished is a descriptive memory based on the experience gained during my stay in a construction company. The main purpose is to shape the most profitable, relevant and disturbing aspects as a result of from my development of nearly six months in the company. It all started when my studies were coming to an end. I had work in design part before, and I was offered to stay with the company and perform my practices with them. Their intention is to form from the beginning the student. In this way, it will acquire the methodology, the customs, the standards of a good realization, the organisational criteria, among others, of the company. And, therefore, the profile created is appropriate to the self-interest of the company, with the mark of the virtues and flaws. I had a great interest in doing the practice in a construction company. And so began our relationship. This was my first professional experience as a trainee assistant and surrounded by professionals in the sector. Obras y construcciones Casil Balear S.L., is a construction company with a trajectory of more than fifteen years located in Palma de Mallorca. Its main activity is the study, the management and the realization of projects and the rehabilitation of some properties. The conservation and restoration of historical and artistic heritage, as well as the detection, analysis and repair of existing pathologies in buildings. My incorporation as a collaborator at the Casil Balear began in the end of 2017 June, thanks to the educational cooperation agreement that my school allows. During my stay in the company my main task has been to follow up the construction of a building of houses multifamily of three heights and a commercial premises, in the street Alexandre Rossello Avenue of Palma de Mallorca. Although this was what I was destined to do, I had the opportunity to have mobility to other interventions that were done simultaneously around Barcelona. In the following lines, I will do a quick review on them: 1) Execution of a 7-storey housing building and a commercial premises. I started my stay on the technical team on the stage of locks and interior liners, and I ended up giving the job to the property. I have collaborated in the organization of the execution, the industrial hiring, the quantity survey, participating in the weekly visits of the work direction, elaborate contradictory prices, revisions at the end of the work, among others. 2) Rehabilitation of a two-storey house in the historic centre of Palma de Mallorca This intervention began in June 2017. This project is an adaptation of a building with a residential use. To carry it out, it is necessary to carry out a set of actions of rehabilitation due to the state of the building and to other factors. I participated in the reconsideration of the divisions and in the control of the execution of the structural reinforcement. I helped with the introduction of materials to work and follow-up in the constructive process. It is a work with a material execution budget of €300,000 and an estimated duration of 3 months. 3) New work in Son Vida, a practically new urbanization, of high adquisitive power in which we had to intervene directly in the mountain, drilling with specific machinery, to achieve the desired staggering to be able to settle the house with safely. This work allowed me to follow construction processes from the beginning, like excavation, foundation among other things. It is a project with a budget of almost €3 million and an expected duration of 8 months. With all these projects and their development, I have been able to analyze different work methodologies, as well as different ways of organizing the work according to their volume, morphological and logistical conditions, and the requirements and terms of the property. I have also been able to see the different actions and needs to be done for a new construction and what is that need to be done when an adaptation. All the points mentioned will be analyzed and commented according to the feelings and experiences acquired.