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The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA-phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA-phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radiopure NaI(Tl) target. The modulation amplitude of thesingle-hitevents in the (2–6) keV energy interval is0.0112±0.0012 cpd/kg/keV; the measured phase is144±7days and the measured period is0.998±0.002 yr; values are in a good well in agreement with those expected for DM particles. No systematic or side reactions able to mimic the exploited DM signature have been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA-phase2 are outlined.

The about 100 kg highly radiopure NaI(Tl) set-up of the DAMA project (DAMA/NaI) took data over seven annual cycles up to July 2002 and has achieved results on various rare processes. Its main aim has actually been the exploitation of the model independent WIMP annual modulation signature. After this conference the total exposure, collected during the seven annual cycles, was released. This cumulative exposure (107731 kg day) has given a model independent evidence for the presence of a Dark Matter particle component in the galactic halo at 6.3 sigma C.L.; this main result is summarised here. Some of the many possible corollary model dependent quests for the candidate particle are mentioned. At present, after about five years of new developments, a second generation low background set-up (DAMA/LIBRA with a mass of about 250 kg NaI(Tl)) was built and is taking data since March 2003. New R&D efforts toward a possible NaI(Tl) ton set-up, we proposed in 1996, have been funded and started in 2003., Contributed paper to the Conf. "Beyond the Desert 03", Rindberg Castle, Germany, June 2003

The DAMA project is an observatory for rare processes and it is operative deep underground at the Gran Sasso National Laboratory of the I.N.F.N. In particular, the DAMA/LIBRA (Large sodium Iodide Bulk for RAre processes) set-up consists of highly radiopure NaI(Tl) detectors for a total sensitive exposed mass of ≊ 250 kg. The results, obtained by this set-up by exploiting the model independent annual modulation signature of Dark Matter (DM) particles, have confirmed and improved those obtained by the former DAMA/NaI experiment. A model independent evidence for the presence of Dark Matter particles in the galactic halo is cumulatively obtained at 8.2 σ C.L. No systematics or side reactions able to account for the measured modulation amplitude and to contemporaneously satisfy all the many specific requirements of the signature have been found or suggested by anyone over more than a decade. Future perspectives are shortly addressed.

In this conference the model-independent result on the presence of dark-matter paticles in the galactic halo obtained over seven annual cycles by the 100kg highly radiopure NaI(T1) DAMA/NaI has been presented and several corollary investigations have also been discussed. More recently the model-independent result obtaind over the first four annual cycles by the second generation 250kg highly radiopure NaI(T1) DAMA/LIBRA set-up at the Gran Sasso National Laboratory of the INFN has also been released. Both the experiments have the unique feature to effectively investigate the presence of dark-matter particles in the galactic halo by exploiting the model-independent annual modulation signature. The data collected by the two experiments over elevn annual cycles for a total exposure of 0.82ton x y have pointed out at 8.2 sigma CL a positive result; several corollary model-dependent quests for the candidate particle(s) and related astrophysical, nuclear and particle physics scenarios are under updating. The future experimental activity can give rise to many new interesting results.