All great answers!!
Stop the madness with foam rolling..It sn’t the magic end all. There also is no scientific research backing up that ART can fix someone with piriformis syndrome in 4-6 visits.
The client needs to be thoroughly assessed by a physiotherapist where the appropriate modalities, manual therapy, stretching and strengthening is applied based on the subjective examination, physical examination and clinical findings.
Once the client is without symptoms, radicular symptoms(typically shooting pain or numbness along the posterior) leg or can be without parasthesias and just localized pain, they need special exercise programming.
Stretching their hip flexors, ITB and hamstrings which will all help prevent balance within the lumbo-pelvic junction. Strengthening their core beginning with static exercises such as bridging, quadruped, standing trunk rotation with cable are all effective exercises that are safe. Progressing to dynamic exercises such as bridging with ball, prone alternate arm and alternate leg lift while lying face down on the ball.
Use of eliptical machine to lengthen the hamstring biomechanically, and to walk in the water is very very therapeutic while strengthening the core and progressing to light jogging can not only be fun but a safe workout!
Don’t forget to strengthen the upper body and weak links-rhomboids, low traps and the lower body weak links-glute medius and minimus whose role is to stabilize in the frontal plane. This can be done with body weight side step lunges and progresses to adding theratubing around the hip proximally.
Remember your anatomy and biomechanics and the client will have a nice and safe transition from physiotherapy to working with you.