In an unstable context characterized by the turbulence of markets and the competitive pressures, the firm is forced to adopt a strategy of development to rema in co mpetitive. The me mbe rship of Algeria to several global organizations imposes on the Algerian company a need for particular adaptation. New challenges await the Algerian firm, changes generated by the liberation of exchange and world co mpetition. To improve its co mpetitiveness to prepare for international competition, this article proposes an adaptation of the management system of the A lgerian firm through a Lean Manufacturing tool, the 5S method. The 5S tool improves productivity because it is designed to check the manufacturing process and ensure that dysfunctions are identified and dealt. The validation of the 5S method was tried on essential equipment in the gas Algerian co mpany. Every "S" is applied to every dysfunction of this equip ment found fro m the Ishikawa diagram and the results are proposed solutions or actions that will allow an imp rovement of the production process by elimination of the wasting and therefore improve the competit iveness of this company.

To get ready for the hard international competition, firms have to convince themselves of the pressing necessity of optimizing its competitiveness factors. In this perspective, this article proposes a general model of management system of firms through the implementation of tools of Lean Manufacturing. This method establishes an approach to introduce an action plan to improve the performance of a firm. Knowing that the Algerian firms do not escape the constraints of competitiveness, the adopted model is applied to two strategic firms of the Algerian industry and the final result gives a series of measures to improve their competitiveness and their performances, simultaneously.

Faced with health pandemic, companies producing goods and / or services must continue their activities to ensure their sustainability. They must organize accordingly by putting in place an organization and working means and hygiene in the company remains the most effective means of preventing risks. In this context, this article proposes implementation of a behavior hygiene and prevention model during the COVID-19 and post COVID-19 periods. Indeed, preserving human potential in the workplace is a fundamental performance lever to boost economy and company must take appropriate preventive measures. The adopted approach is based on the 5S method, which the main objective is continuous improvement of company's activities, thus offering an adequate solution to reduce risks in terms of health and safety. Besides the economic aspect, the proposed sustainable model is also part of pedagogical perspective for educating the population over time.