In Europe, the modus operandi of this new brand of thief will include planting "bugs" in software, using occurrences of computer crashes to create money-making opportunities, using his credibility to gain access to a bank's proprietary management information and trading software, and using his knowledge of specific programs to take advantage of software arbitrage opportunities. The most fertile field for planting a computer bug is in off-balance sheets and derivative instruments; this is where such a crime will be hardest to trace and potentially most profitable. Through this ploy, the software criminal can profit directly from the markets or by selling information to competing banks. Although almost computer software programs contain some bugs, a lack of sophistication in bank management as well as lack of quality control in third-party, software house products have made solutions hard to find. While some software houses are installing security aspects in their system, a lack of proper audit trails makes computer crimes hard to detect. And as banks buy computer expertise, the gap in knowledge between bank managers and software developers will grow to give software criminals and outside consultants greater opportunities for fraud.