In general, it refers to a collateralization technique that enables an entity to make collateral available to a counterparty without earmarking it (i.e., without allocating it to a specific transaction).

In a different context, specifically, with respect to securitization, a collateral pool provides the cash flows used to service asset-backed securities (ABS)- broadly, collateralized debt obligations (CDOs)- and credit quality of the pools is therefore a key concern for holders of such securities. The composition of a collateral pool determines the nature of the securities in question. For example, if a collateral pool only consists of bonds or debt instruments, then the obligation is known as a collateralized bond obligation (CBO).

In the latter sense, collateral pools can either be actively traded or not. CDOs can be classified into cash flow CDOs and market value CDOs. The collateral of a market value CDO can be actively traded, as opposed to that of cash flow CDOs where the par amount of the collateral securities is used to determine the portfolio value of a cash flow CDO.