An immunoconjugate having the formula Ab-(L-D)p, wherein: (a) Ab is the antibody; (b) L is a linker; (c) D is the cytotoxic agent; and (d) p ranges from 1-8; wherein D has a structure selected from: and and Ab is an antibody that binds human CD79b, wherein the antibody comprises: a) (i) HVR-H1 comprising the amino acid sequence of SEQ ID NO: 21, (ii) HVR-H2 comprising the amino acid sequence of SEQ ID NO: 22, and (iii) HVR-H3 comprising the amino acid sequence of SEQ ID NO: 23; (iv) HVR-L1 comprising an amino acid sequence selected from SEQ ID NOs: 18, 24, and 35, (v) HVR-L2 comprising the amino acid sequence of SEQ ID NO: 25, and (vi) HVR-L3 comprising the amino acid sequence of SEQ ID NO: 26; or b) (i) HVR-H1 comprising the amino acid sequence of SEQ ID NO: 21, (ii) HVR-H2 comprising the amino acid sequence of SEQ ID NO: 22, and (iii) HVR-H3 comprising the amino acid sequence of SEQ ID NO: 23; (iv) HVR-L1 comprising the amino acid sequence of SEQ ID NO: 24, (v) HVR-L2 comprising the amino acid sequence of SEQ ID NO: 25, and (vi) HVR-L3 comprising the amino acid sequence of SEQ ID NO: 26; or c) a VH sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 11; or d) a VL sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 12; or e) a VH sequence as in (c) and a VL sequence as in (d); f) a VH sequence having an amino acid sequence selected from SEQ ID NOs: 9, 11, and 13; or g) a VL sequence having an amino acid sequence selected from SEQ ID NOs: 8, 10, 12, and 14; or h) a VH sequence as in (f) and a VL sequence as in (g); or i) a VH sequence having the amino acid sequence of SEQ ID NO: 11; or j) a VL sequence having the amino acid sequence of SEQ ID NO: 12; or k) a VH sequence as in (i) and a VL sequence as in (j). (a) Ab is the antibody; (b) L is a linker; (c) D is the cytotoxic agent; and (d) p ranges from 1-8; a) (i) HVR-H1 comprising the amino acid sequence of SEQ ID NO: 21, (ii) HVR-H2 comprising the amino acid sequence of SEQ ID NO: 22, and (iii) HVR-H3 comprising the amino acid sequence of SEQ ID NO: 23; (iv) HVR-L1 comprising an amino acid sequence selected from SEQ ID NOs: 18, 24, and 35, (v) HVR-L2 comprising the amino acid sequence of SEQ ID NO: 25, and (vi) HVR-L3 comprising the amino acid sequence of SEQ ID NO: 26; or b) (i) HVR-H1 comprising the amino acid sequence of SEQ ID NO: 21, (ii) HVR-H2 comprising the amino acid sequence of SEQ ID NO: 22, and (iii) HVR-H3 comprising the amino acid sequence of SEQ ID NO: 23; (iv) HVR-L1 comprising the amino acid sequence of SEQ ID NO: 24, (v) HVR-L2 comprising the amino acid sequence of SEQ ID NO: 25, and (vi) HVR-L3 comprising the amino acid sequence of SEQ ID NO: 26; or c) a VH sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 11; or d) a VL sequence having at least 95% sequence identity to the amino acid sequence of SEQ ID NO: 12; or e) a VH sequence as in (c) and a VL sequence as in (d); f) a VH sequence having an amino acid sequence selected from SEQ ID NOs: 9, 11, and 13; or g) a VL sequence having an amino acid sequence selected from SEQ ID NOs: 8, 10, 12, and 14; or h) a VH sequence as in (f) and a VL sequence as in (g); or i) a VH sequence having the amino acid sequence of SEQ ID NO: 11; or j) a VL sequence having the amino acid sequence of SEQ ID NO: 12; or k) a VH sequence as in (i) and a VL sequence as in (j).