A nucleic acid molecule, binding to SDF-1, comprising in 5'->3' direction a first stretch of nucleotides, a core nucleotide sequence and a second stretch of nucleotides, or a second stretch of nucleotides, a core nucleotide sequence and a first stretch of nucleotides, whereby the length of the nucleic acid molecule is 20 to 50 nucleotides, whereby the nucleic acid molecule is selected from the group consisting of type A nucleic acid molecules, type B nucleic acid molecules, type C nucleic acid molecules and nucleic acid molecules having a nucleic acid sequence according to any of SEQ.ID.No. 142, SEQ.ID.No. 143 and SEQ.ID.No. 144; whereby the type A nucleic acid molecules comprise the following core nucleotide sequence: 5' AAAGYRACAHGUMAAX A UGAAAGGUARC 3' (SEQ.ID. 19) whereby X A is either absent or is A, and whereby the first stretch of nucleotides of the type A nucleic acid molecules comprises a nucleotide sequence of 5' X 1 X 2 NNBV 3' (SEQ.ID.No. 44) and the second stretch of nucleotides of the type A nucleic acid molecules comprises a nucleotide sequence of 5' BNBNX 3 X 4 3' (SEQ.ID.No. 45), whereby X 1 is either absent or R, X 2 is S, X 3 is S and X 4 is either absent or Y, or X 1 is absent, X 2 is either absent or S, X 3 is either absent or S and X 4 is absent; whereby the type B nucleic acid molecules comprise the following core nucleotide sequence: 5' GUGUGAUCUAGAUGUADWGGCUGWUCCUAGUYAGG 3' (SEQ.ID.No. 57), and whereby the first stretch of nucleotides of the type B nucleic acid molecules comprises a nucleotide sequence of 5' X 1 X 2 SVNS 3' (SEQ.ID.No. 77) and the second stretch of nucleotides of the type B nucleic acid molecules comprises a nucleotide sequence of 5' BVBSX 3 X 4 3' (SEQ.ID.No. 78), whereby X 1 is either absent or is A, X 2 is G, X 3 is C and X 4 is either absent or is U, or X 1 is absent, X 2 is either absent or is G, X 3 is either absent or is C and X 4 is absent; whereby the type C nucleic acid molecules comprise a core nucleotide sequence of GGUYAGGGCUHRX A AGUCGG (SEQ.ID.No.90), whereby X A is either absent or is A, and whereby the first stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' RKSBUSNVGR 3' (SEQ.ID.No. 120) and the second stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' YYNRCASSMY 3' (SEQ.ID.No. 121), or whereby the first stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' XsSSSV 3' (SEQ.ID.No. 124) and the second stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' BSSSXs 3' (SEQ.ID.No. 125), whereby X s is either absent or is S, or whereby the first stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' UGAGAUAGG 3' and the second stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' CUGAUUCUCA 3', or whereby the first stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' GAGAUAGG 3' and the second stretch of nucleotides of the type C nucleic acid molecules comprises a nucleotide sequence of 5' CUGAUUCUC 3'. 5' AAAGYRACAHGUMAAX A UGAAAGGUARC 3' (SEQ.ID. 19) 5' GUGUGAUCUAGAUGUADWGGCUGWUCCUAGUYAGG 3' (SEQ.ID.No. 57), and GGUYAGGGCUHRX A AGUCGG (SEQ.ID.No.90),