Inclusion Criteria:

- Patients aged 18 years and older.

- Histologically confirmed diagnosis of melanoma

- Previously treated or previously untreated stage IV melanoma by AJCC staging criteria

- Presence of an index lesion between 1 cm and 5 cm.

- EGOC performance status 0 to 1

- Signed informed consent document.

- Adequate renal, hepatic, and hematologic indices for ipilimumab therapy

- Ability to tolerate stereotactic body radiation therapy (e.g. lie flat and hold
position for treatment)

Exclusion Criteria:

- Prior systemic therapy within 28 days of study enrollment

- Clinical contraindication to stereotactic body radiotherapy (e.g.active systemic
sclerosis, active inflammatory bowel disease if bowel is within target field, etc)

- Previous treatment with antiCTLA-4 antibody or cancer vaccine

- Presence or history of central nervous system metastasis (including brain)

- Long-term use of systemic corticosteroids

- Prior RT within 2 months of study entry