A total of 1,540 crossbreed pigs of similar origin and production conditions (weaned 28 d, slaughtered 100 kg BW) were used in 3 experiments to assess on the implementation of a traceability system based on electronic identification (e-ID) and molecular markers (DNA). Pigs were tagged by 3 types of electronic ear tags and carcasses audited by DNA. In Exp. 1, piglets (n = 1,033) were e-ID at birth with ear tags (EF1, plastic double button FDX-B transponder, 2.6 g), biopsied (n = 30) and slaughtered under commercial conditions. No EF1 losses were reported until weaning, but fattening losses were 6.3%. Losses of EF1 during transportation and slaughtering were 41.9%, resulting in 52.8% overall traceability. Auditing 18 carcasses by a panel of 12 DNA microsatellites showed 83.3% of compliance. In Exp. 2, 133 weaned piglets were e-ID (EH, plastic double button HDX transponder, 4.4 g) and biopsied (n = 56). Fattening and slaughtering were done under experimental conditions. Onfarm losses were 1.5% and 0.8% losses were observed at slaughter, overall traceability being 97.7%. Auditing 56 carcasses by DNA microsatellites showed 98.2% of compliance. In Exp. 3, 374 weaned piglets were e-ID with 453 ear tags of 3 types: EF1 (n = 151), EF2 (plastic double button FDX-B transponder, 4.2 g; n = 140) and EH (n = 162). Biopsies for auditing were 97. Fattening was done in the farm of Exp. 1 and slaughtering in 3 commercial slaughterhouses. By ear tag type (EF1, EF2 and EH), on-farm losses were 0, 1.9 and 0.9%, and failures 5.0, 5.6 and 0.9%. On-farm traceability was 95.0, 92.5 and 98.2% (the last differing at P < 0.05), respectively. Additionally 5.3, 5.0 and 1.8 % ear tags were lost or failed during transportation, respectively. Slaughtering losses were 22.1, 13.5 and 4.5% and failures were 6.3, 5.4 and 0%, resulting in 71.6, 81.1 and 95.5% slaughterhouse traceability, respectively. Overall traceability was 64.4, 71.2 and 92.1 for EF1, EF2 and EH, respectively (P < 0.05). Auditing 12 carcasses by DNA microsatellites resulted in 85.7% of compliance. Ten samples of each ear tag type were collected across the experiments for studying their features and performances under laboratory conditions. Separation strength of EF1 from Exp. 1 was weaker (P < 0.05) than the rest of ear tags and reading distances varied dramatically according to the reader, technology and orientation towards the antenna used (0.3 to 33.4 cm). In conclusion, the EH ear tags were more efficient than EF1 and EF2 for tracing pigs under commercial conditions. On-farm traceability depended on device used and fattening and slaughtering conditions. Traceability auditing by DNA varied by sample quality and matching rates ranged between 88.2 and 98.2%. In conclusion, the use of quality electronic ear tags and DNA analysis are recommended for implementing a traceability system in the pig industry. Finally, a sociological case study of a particular livestock sector in France, wich is currently reluctant to the use of electronic identification, was conducted with the aim of completing the vision of this technology in the livestock industry.