Inclusion Criteria:

* Participant has signed and dated the appropriate Informed Consent document.
* Female participant is ≥ 18 years of age.
* Currently using an approved method of birth control, or surgically sterile, or of non-child bearing age with no menstrual period for the past year.
* Participant has a clinical diagnosis of IC/PBS in the opinion of the investigator.
* Participant with IC/PBS has reported a bladder pain/discomfort score of 3 or greater on a 0-10 Likert scale over the previous four weeks. This bladder pain/discomfort criterion must be met at each of the two baseline screening visits as reported by the participant.
* Participant with IC/PBS has reported a symptom score of abnormal urinary frequency of 3 or greater on a 0-10 Likert scale over the previous four weeks. This frequency criterion must be met at each of the two baseline screening visits, as reported by the participant.
* Participant has had symptoms of discomfort or pain in the pelvic region for at least a three (3) month period within the last six (6) months.
* Current symptoms have been present for less than 3 years. If similar symptoms were present in the past, they must have been completely resolved for at least one year prior to onset of current symptoms.
* Participant has previously undergone at least one course of therapy (other than physical therapy) for her symptoms.
* Presence of tenderness/pain to palpation found by the physician in one of the pelvic floor musculature domains during the first baseline screening visit physical examination which are confirmed by the physical therapist at screening visit 2. Presence of tenderness/pain is defined as a mild, moderate or severe finding by the physician at visit 1 and physical therapist at visit 2. The pelvic floor musculature domains are defined as: anterior or posterior levator muscles, obturator internus muscles and urogenital diaphragm (bulbospongiosus, superficial transverse perinei, ischiocavernosus, central tendon/perineal body). The assessment of tenderness/pain at Visits 1 and 2 do not need to be identical in severity or location in order for the participant to be eligible.

Exclusion Criteria:

* Participant has relevant, painful scars on lower abdominal wall that, in the opinion of the study physician or physical therapist, is unlikely to respond to physical therapy without adjuvant therapy such as injection /needling.
* A positive urine culture (defined as >100,000 CFU/ml) is exclusionary. A negative urine culture within 1 month of study enrollment is acceptable.
* Participant is unable to tolerate insertion of one or two vaginal examining fingers (e.g. vulvar allodynia), or one rectal examining finger.
* Participant had prior course of physical therapy that included manual therapy with connective tissue manipulation by physical therapist for same symptoms. Prior treatment by therapist with biofeedback, electrical stimulation, or pelvic floor exercises is not exclusionary.
* Participant has relevant neurologic disorder that affects bladder and/or neuromuscular function in the opinion of the investigator.
* Participant has active urethral or ureteral calculi, urethral diverticulum.
* Participant has a history of pelvic radiation therapy, tuberculous cystitis, bladder cancer, carcinoma in situ, or urethral cancer.
* Participant has/reports any severe debilitating or urgent concurrent medical condition.
* Participant has a potentially significant pelvic pathology or abnormalities on examination or prior imaging, including prolapse beyond the hymenal ring, pelvic mass, etc. that could cause or contribute to the clinical symptoms or require treatment.
* Participant is unlikely to be compliant due to unmanaged medical or psychological condition, including neurological, psychological or speech /language problems that will interfere with her ability to complete the study.
* Participant has an imminent change in residence or other social factors that could compromise compliance with the protocol.
* Pregnancy or refusal of medically approved/reliable birth control in women of child-bearing potential.
* Participant has pain, frequency, urgency symptoms present only during menses.