Inclusion Criteria:

1. Up to 70 years of age .
2. B-cell lymphoid malignancies (those with CD20 negative disease at their diagnosis will not receive rituximab): This includes CLL/small lymphocytic lymphoma, follicular lymphoma, mantle cell, diffuse large cell, Splenic lymphoma, MALT, lymphoplasmacytic lymphoma and Burkitt's lymphoma.
3. Patients in relapse or considered at high risk for relapse.
4. In order to increase the chance of KIR-mismatching between recipient and donor, a 9/10 matched (mismatched locus C ) unrelated donor would be preferable. If a mismatched donor is not available, then a fully-matched unrelated donor or other 9/10 matched unrelated donor will be considered.
5. A sibling donor who is 9/10 matched may also be allowed.
6. Zubrod PS </= 2.
7. Left ventricular EF >/= 40% with no uncontrolled arrythmias or symptomatic heart disease.
8. FEV1, FVC and DLCO >/= 50%.
9. Serum creatinine < 1.8 mg/dL. Serum bilirubin < 3X upper limit of normal,
10. AST < 3X upper limit of normal.
11. Signed, written IRB-approved informed consent.
12. Men and women of reproductive potential must agree to follow accepted birth control methods for the duration of the study. Female subject is either post-menopausal or surgically sterilized or willing to use an acceptable method of birth control (i.e., a hormonal contraceptive, intra-uterine device, diaphragm with spermicide, condom with spermicide, or abstinence) for the duration of the study. Male subject agrees to use an acceptable method for contraception for the duration of the study.

Exclusion Criteria:

1. Past history of anaphylaxis following exposure to CAMPATH-IH or Rituximab
2. Patient with active CNS disease.
3. Positive Beta HCG text in a woman with child bearing potential defined as not post-menopausal for 12 months or no previous surgical sterilization, or currently breast-feeding.
4. Known infection with HIV, HTLV-I, Hepatitis B, or Hepatitis C.
5. Patients with other malignancies diagnosed within 2 years prior to Study registration (except skin squamous cell carcinoma).
6. Active uncontrolled bacterial, viral or fungal infections.
7. Major surgical procedure or significant traumatic injury within 4 weeks prior to Study registration.
8. Serious, non-healing wound, ulcer, or bone fracture.
9. History of abdominal fistula, gastrointestinal perforation, or intra-abdominal abscess within 6 months prior to Study registration.
10. History of Stroke within 6 months.
11. Myocardial infarction within the past 6 months prior to Study registration.
12. Uncontrolled chronic diarrhea.
13. A prior allogeneic transplant from the same donor. Is there an age limit? Yes