The main objective of my research activity is the development and the experimental analysis of efficient techniques of domain independent planning, which proposes to identify a partially ordered set of actions whose execution allows one or more agents to reach their goals starting from a specific initial situation. My research has been focused on generic algorithms that can be applied to a variety of situations in which the evolution of the external world makes it necessary to revise a plan which has been previously formulated or the generation of a new plan. In such a context I have developed the systems LPG, LPG-td and ADJ together with Prof. Alfonso Gerevini and other members of the AI group of the University of Brescia. In particular LPG is at present one of the best domain independent planners that exist in terms of execution times, quality of the plans produced and expressivity of manageable problems. LPG took part in the third International Planning Competition IPC3 obtaining the award “distinguished performance of the first order”. LPG-td has been awarded in the fourth International Planning Competition IPC4 in the Suboptimal Metric Temporal Track. LPG-td is an extension of the LPG planner that can handle most of the features of PDDL2.2, the standard planning language of the 4th International Planning Competition (IPC-4).