It all started when, as a fourth year medical student, one of us suffered from Achilles tendinopathy as the result of too much running, and we realized how little science existed on the topic It was the begiагтзнnning of a wonderful, neverending relationship, always involving new materials, and never boring The tendo Achillis is the largest and strongest tendon in the body—and the most frequently injured The fact that it causes much aggravation had long been recognized, and агшэрthe amount of clinical and basic science work performed on it is phenomenal Nevertheless, we still lack evidence-based guidelines for best practices Some authors are very sanguine about their views Others keep an open mind and continue to perform hypothesis tensing-based studies The tendon is subjected to overuse and acute injuries We have put together a multicontinental team to tackle a variety of issues on the Achilles tendon We believe that we have covered most of the bases fагыьчrom the gross anatomy to the more sophisticated vision of the future in which gene therapy and tissue engineering will be in the forefront We learned a lot, but much needs to be done We enjoyed assembling this material, and we hope that readers will benefi t from it.