Treatment of connected person and accommodating party permits treating parties as one and disregarding accommodating parties to prevent tax avoidance. The provision permits, for purposes of determining a tax benefit under the General Anti-Avoidance Rule, treating connected persons as one and the same person, disregarding any accommodating party, treating an accommodating party and any other party as one and the same, and looking through an arrangement by disregarding corporate structure to assess the substance of transactions.