Spasticity is a general term (just like what James was saying), but in this case I think you are referring to hypertonicity, commonly found in hemiplegics and other CNS lesions (head injuries, for instance).
My basic principles for addressing spasticity is:
- maintain ROM (out of the pathological pattern)
- dynamic weightbearing (not STATIC weighbearing)
- retraining of active movements (selectivity) after normalisation of tone
- integration into functional activities (with lots of facilitation and correction if necessary).
This is just a guideline, again, each patient is individualistic (thus, initial & ongoing assessments are essential!) Adapt your treatment/principles according to the assessment (often changes from day to day).