The concept of "soft law" has been familiar for some years, in many areas of law, although its meaning is debated. The distinctive characteristic of "soft law" appears to be the vagueness of the obligations that it imposes or the weakness of its commands. It concerns a legally non-binding sphere. The article examines this notion in the light of the relationship between sources and interpretation. "Soft law" comes to the fore in the discussion on the sources of law, which are connected to interpretation. The term has come to refer to a range of phenomena related to legal positivization and interpretative practice participates constitutively in the process of realization of law. "Soft law" performs various functions. It plays a role in the legal order, which shows a gradual differentiation of its normativity. Normativity is not something that is monolithic. We have a sliding scale of hardness or softness in all norms. So, there is a dynamic interplay between soft and hard law.