TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Proteins: The one or more cellulolytic proteins comprise beta -glucosidase, Trichoderma reesei cellobiohydrolase I (CEL7A), T.reesei cellobiohydrolase II (CEL6A) and T.reesei endoglucanase I (CEL7B). The polypeptide having cellobiohydrolase II activity is CEL6 polypeptide. The CEL6 polypeptide is chosen from polypeptide comprising an amino acid sequence having at least 60% identity to mature polypeptide chosen from one of 5 polypeptide having a 471, 482, 481 or 477 amino acid sequence (SEQ ID NO: 26, 30, 32, 34 or 38) all fully defined in the specification; polypeptide encoded by a polynucleotide that hybridizes under low stringency conditions with (i) the mature polypeptide coding sequence of 1611, 1812, 1725, 1446 or 1593 base pair sequence (SEQ ID NO: 25, 29, 31, 33 or 35) fully defined in the specification, (ii) the genomic DNA sequence comprising or the cDNA sequence contained in the mature polypeptide coding sequence of SEQ ID NO: 25, 29, 31 or 33 or a 1434 base pair sequence (SEQ ID NO: 37) fully defined in the specification, or (iii) complementary strand of (i) or (ii); a polypeptide encoded by a polynucleotide comprising a nucleotide sequence having at least 60% identity to the mature polypeptide coding sequence of SEQ ID NO: 25, 29, 31, 33 or 37; polypeptide comprising the amino acid sequence of SEQ ID NO: 26, 30, 32, 34 or 38; and their fragment. The polypeptide having xylanase activity is GH10 polypeptide. The GH10 polypeptide is chosen from polypeptide comprising amino acid sequence having at least 60% identity to mature polypeptide having a 406, 369, 414, 364, 323, 397 or 403 amino acid sequence (SEQ ID NO: 70, 72, 74, 76, 78, 80 or 99) fully defined in the specification; polypeptide encoded by a polynucleotide that hybridizes under low stringency conditions with (i) the mature polypeptide coding sequence having a 1327, 1110, 1245, 1145, 1400, 1415 or 1387 base pair sequence (SEQ ID NO: 69, 71, 73, 75, 77, 79 or 98) fully defined in the specification, (ii) the genomic DNA sequence comprising or the cDNA sequence contained in the mature polypeptide coding sequence of SEQ ID NO: 69, 71, 73, 75, 77, 79 or 98 or (iii) a full-length complementary strand of (i) or (ii); polypeptide encoded by a polynucleotide comprising a nucleotide sequence having at least 60% identity to the mature polypeptide coding sequence of SEQ ID NO: 69, 71, 73, 75, 77, 79 or 98; polypeptide comprising the amino acid sequence of SEQ ID NO: 70, 72, 74, 76, 78, 80 or 89; and their fragment. The polypeptide having xylanase activity is GH11 polypeptide. The one or more cellulolytic proteins further comprise one or more enzymes chosen from Trichoderma reesei endoglucanase II (CEL5A), T.reesei endoglucanase V (CEL45A) and T.reesei endoglucanase III (CEL12A). The cellulolytic proteins, polypeptide having cellobiohydrolase activity and/or polypeptide having xylanase activity are in the form of a fermentation broth with or without cells. Preferred Composition: The enzyme composition further comprises GH61 polypeptide having cellulolytic enhancing activity. Preferred Method: The steps (a) and (b) are performed simultaneously. The fermentation method further involves recovering the fermentation product from the fermentation. The cellulosic material is pretreated before saccharification.