Nuclear factor kappa B (NF-kappa B) is common proinflammatory transcription factor involved in expression of c.a. 300 different genes. It is usually present in the cytosol as an inactive complex and upon activation translocates into the nucleus. The mechanisms of activation of NF-kappa B are complex and they involve several different signaling pathways and plethora of proteins. In this minireview we describe the main deciphered as well as suggested mechanisms regulating of NF-kappa B activity.