Chronic lymphocytic leukemia (CLL) is a disease of the elderly, with a median age at diagnosis of c.70 years. The natural course of the disease varies greatly, and patients with non-progressive and asymptomatic leukemia do not require treatment. But advanced and progressive CLL do require treatment. The results of CLL treatment have improved significantly in recent years, mainly due to the introduction of new and more effective drugs, including B-cell receptor inhibitors and B-cell lymphoma 2 (BCL2) inhibitors. These new drugs are used continuously as monotherapy, or in combination schemes for specified periods. Venetoclax in combination with anti-CD20 antibodies is used for 24 (rituximab) or 12 (obinutuzumab) months, while treatment with ibrutinib and venetoclax lasts 15 months. The choice of treatment protocol should largely depend on the assessment of 17p deletion/TP53 mutation, and in second treatment line immunoglobulin variable heavy chain (IGVH) mutation status, which correlate with a response to immunochemotherapy. The role played by immunochemotherapy has recently significantly decreased. It is still an option for first line treatment in patients without 17p deletion/TP53 mutation, with mutated gene encoding IGVH and in good performance status. However, the results of recent studies have shown that these patients may also obtain major benefit from chemotherapy-free regimens. The remaining patients, both in the first and subsequent treatment lines, should receive new targeted therapies, which are currently available in Poland under the drug program. In this article, we present an update of the guidelines for the diagnosis and treatment of CLL, including the treatment of autoimmune complications, as well as the prophylaxis and treatment of infections, developed by the Polish Society of Haematologists and Transfusiologists and the Polish Adult Leukemia Group-CLL working group.