Big Data an opportunity for friendly cities Lorena Pocatilu The Bucharest University of Economic Studies, Economic Informatics and Cybernetics Department Bucharest, Romania lorena.pocatilu@ie.ase.ro The use of big data solutions is the biggest opportunity for friendly cities in our years. This happened because we need to access, process and use different data type very fast and big data solutions offers these facilities. The concept of big data which creating value is not new, and in our age the effective use of da-ta is to becoming the basis element of competition. Cities of our time have always wanted to use correctly and to the real value the information and knowledge in order to make better, smarter, real time, fact-based decisions, this necessity of correct knowledge has fueled the growth of using big data. In this case the big data concept is the most important support for cities’ evolutions. In the world, many cities who are agree that this is true aren't sure how to make the most of it implementation. After a literature review analysis, this paper presents the steps for implement the solutions of big data in the core area of cities. More and more companies from business and administration are agree that big data is an op-portunity for friendly cities. This paper highlights with examples from all over the world that those areas which use big data have good results. The areas that succeed aren't the ones who have the most data, but the ones who use it best. Big data will fundamentally change the way cities compete and operate. Companies from business and administration that invest in and successfully derive value from their data will have a distinct advantage over their competitors — a performance gap that will continue to grow as more relevant data is generated, emerging technologies and digital channels offer better acquisition and delivery mechanisms, and the technologies that enable faster, easier data analysis continue to develop. Investment and development are the keys of our cities. This paper presents the impact of the big data solutions and how can use all the facility of this in friendly cities development. Having in view the researches in this area the cities development using big data in accordance with sustainability principles has become an opportunity of this century. An efficient access and use of huge quantity of data through big data solutions and the involvement of citizens in the initi-atives of local communities are the key elements that a city can use to achieve a harmonious development. The major research of this approach is centered on the necessity of use big data for friendly cities.