A Somatostatin receptor ligand, consisting of: a peptide moiety or an amide form thereof, said peptide moiety consisting of an amino acid residue sequence selected from the group consisting of: Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:14); Arg-Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:15); DPhe-Arg -Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:16); Cys-Phe-Trp-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:19); DPhe-Cys-Phe-Trp-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:20); Cys-Tyr-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:23); DPhe-Cys-Tyr-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:24); Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:27); Arg-Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:28); DPhe-Arg-Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:29); Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:32); Arg-Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:33); DPhe-Arg-Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:34); Cys-Tyr-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:37); DPhe-Cys-Tyr-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:38); Cys-Arg-Phe-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:43); DPhe-Cys-Arg-Phe-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:44); Cys-Arg-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:48); DPhe-Cys-Arg-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:49); DPhe-HCys-Phe-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:51); DPhe-DCys-Phe-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:53); Cys-Phe-Trp-DTrp-Aib-Thr-Phe-GlyS2 (SEQ ID NO:56); DPhe-Cys-Phe-Trp-DTrp-Aib-Thr-Phe-GlyS2 (SEQ ID NO:57); Cys-Phe-Trp-DTrp-LysAc-Thr-Phe-GlyS2 (SEQ ID NO:60); DPhe-Cys-Phe-Trp-DTrp-LysAc-Thr-Phe-GlyS2 (SEQ ID NO:61); DPhe-Cys-Phe-Trp-DTrp-Arg-Thr-Phe-GlyS2 (SEQ ID NO:63) Cys-Phe-Trp-DTrp-HomoLys-Thr-Phe-GlyS2 (SEQ ID NO:66); and DPhe-Cys-Phe-Trp-DTrp-HomoLys-Thr-Phe-GlyS2 (SEQ ID NO:67) wherein GlyS2 is N(CH2CH2S-)CH2CO-: and wherein said selected amino acid residue sequence is cyclized with a sulfur-sulfur bond between said sulfur atom of GlyS2 and a sulfur atom of a Cysteine moiety, of said selected amino acid residue sequence,; and optionally at least one active agent moiety covalently bonded to said peptide moiety, or bonded indirectly to the terminal nitrogen atom of an N-terminal amino acid residue of said peptide moiety through a linker; wherein the active agent moiety is selected from the group consisting of: an imaging moiety, a therapeutic moiety, a dye, a fluorescent moiety, a toxin, a chelator, a moiety with a metal atom, a moiety with a radioactive atom, a nanoparticle, an ethylene glycol polymer, photosensitizer, a liposome constituent and a micelle constituent. Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:14); Arg-Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:15); DPhe-Arg -Cys-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:16); Cys-Phe-Trp-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:19); DPhe-Cys-Phe-Trp-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:20); Cys-Tyr-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:23); DPhe-Cys-Tyr-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:24); Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:27); Arg-Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:28); DPhe-Arg-Cys-Phe-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:29); Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:32); Arg-Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:33); DPhe-Arg-Cys-Tyr-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:34); Cys-Tyr-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:37); DPhe-Cys-Tyr-DTrp-Orn-Thr-Phe-GlyS2 (SEQ ID NO:38); Cys-Arg-Phe-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:43); DPhe-Cys-Arg-Phe-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:44); Cys-Arg-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:48); DPhe-Cys-Arg-Phe-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:49); DPhe-HCys-Phe-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:51); DPhe-DCys-Phe-Trp-DTrp-Lys-Thr-Phe-GlyS2 (SEQ ID NO:53); Cys-Phe-Trp-DTrp-Aib-Thr-Phe-GlyS2 (SEQ ID NO:56); DPhe-Cys-Phe-Trp-DTrp-Aib-Thr-Phe-GlyS2 (SEQ ID NO:57); Cys-Phe-Trp-DTrp-LysAc-Thr-Phe-GlyS2 (SEQ ID NO:60); DPhe-Cys-Phe-Trp-DTrp-LysAc-Thr-Phe-GlyS2 (SEQ ID NO:61); DPhe-Cys-Phe-Trp-DTrp-Arg-Thr-Phe-GlyS2 (SEQ ID NO:63) Cys-Phe-Trp-DTrp-HomoLys-Thr-Phe-GlyS2 (SEQ ID NO:66); and DPhe-Cys-Phe-Trp-DTrp-HomoLys-Thr-Phe-GlyS2 (SEQ ID NO:67) and wherein said selected amino acid residue sequence is cyclized with a sulfur-sulfur bond between said sulfur atom of GlyS2 and a sulfur atom of a Cysteine moiety, of said selected amino acid residue sequence,; and optionally at least one active agent moiety covalently bonded to said peptide moiety, or bonded indirectly to the terminal nitrogen atom of an N-terminal amino acid residue of said peptide moiety through a linker; wherein the active agent moiety is selected from the group consisting of: an imaging moiety, a therapeutic moiety, a dye, a fluorescent moiety, a toxin, a chelator, a moiety with a metal atom, a moiety with a radioactive atom, a nanoparticle, an ethylene glycol polymer, photosensitizer, a liposome constituent and a micelle constituent.