Avoiding transactions without consideration or with insignificant consideration has not yet been meaningfully disputed in Serbian theory of bankruptcy law. Practitioners and academics usually conclude that this type of avoidance is uncontroversial and does not raise problems in practice. This paper is trying to show that such conclusion is not justified, and most probably is a consequence of infrequent use of this type of avoidance. Writing of this paper is particularly justified by the fact that the new Bankruptcy Act has partially changed national regulation of this question. In introductory part of the paper, the author identifies basic, open and partially unresolved questions related to avoiding transactions without consideration or with insignificant consideration, for which comparative bankruptcy legislations provide for no uniform answers. The second part of the paper examines the purpose of this type of avoidance, and concludes that principal justification is the amelioration of perverse incentives in the period leading up to bankruptcy. The third part of the paper deals with the boundaries of transactions without consideration and with insignificant consideration, a question that can raise many problems in practice. Taking into consideration that transaction must be entered into by the debtor at a relevant time before bankruptcy, the following part of the paper examines the temporal and financial aspect of the relevant period. Finally, the paper examines some of the most significant exemptions of general rules on avoidance of transactions without consideration or with insignificant consideration.