I have benefitted tremendously from dry needling during physical therapy. It was a key part of my treatment.  The following is quoted from other commenters, but reflects my understanding of the practice as clearly explained to me by my physical therapist prior to beginning treatment AND as verified by my own independent research before beginning treatment. 

"Trigger Point Dry Needling IS NOT Accupuncture!!

Physical Therapists possess the anatomical, physiological and clinical knowledge to perform trigger point dry needling safely and effectively. Physical Therapists are highly educated and trained healthcare professionals who specialize in treating the neurological, muscular and skeletal movement systems via many modalities and dry needling is one such modality. 

Trigger point dry needling is distinctly different from acupuncture as the treatment goal and method is different.  While both practices may use a similar implement or device, the clinical reasoning, technique, and goal of the treatment are different. 

The regulations proposed by the Virginia Board of Physical Therapy are sufficient to ensure public safety and should be fully enacted."