Urban spaces are responsible for many environmental, social and economic challenges in today,s society. Attending to UN projections, it is expected that cities, problems tend to increase, worsening some urban indicators such as waste and water management, resources consumption, land use and cover. To tackle these issues, new approaches should be undertaken, gathering all fields of study, including civil engineering, due to its preponderance in the city,s systems. Construction activities and urban mobility represent two sectors with the highest ecological footprint, while water and waste management are crucial for citizen health and security. This communication presents some of the most recent proposals studied and implemented to improve city sustainability in the fields previously mentioned: low-carbon and low-cement concrete have been developed in the last few years to reduce carbon emissions to the atmosphere; byproducts have been tested to substitute natural resources in construction materials; models of water supply networks have been improved to minimise leaks and water shortage; and decision tools have been developed to optimise urban planning and transportation. Despite the diversity of topics, the need for a holistic view of the city is pointed out as an added value for smart and sustainable city management.