在《领导力21法则》中，有许多关键的法则，但如果要选择其中最重要的三个法则，我会选择以下法则：

1. **条法则：想象一个未来的成功，然后把每天的决策和行动与这个愿景对比。这个法则强调了领导者的远见和目标导向性。领导者需要能够清晰地想象未来的成功，并将每天的决策和行动与这个愿景对比，以确保他们的行动都朝着实现这个目标的方向努力。这个法则提醒领导者需要有清晰的愿景，并将其传达给团队，以激励和引导他们朝着共同目标前进。

2. 第二条法则：团队和合作至关重要。这个法则强调了领导者需要与团队紧密合作的重要性。没有任何人可以单独成功，成功是团队的成果。领导者需要懂得建立和管理团队，培养良好的团队合作氛围，以实现共同目标。他们需要赋予团队成员信任和责任，并促进有效的沟通和协作，以达到团队的**表现。

3. 第十八条法则：接受挑战。在取得成功之前，需要不断地学习和成长，接受挑战并克服障碍。这个法则强调了领导者需要具备适应变化和克服困难的能力。领导者应该持续学习和发展自己的技能和知识，以应对不断变化的环境和挑战。他们需要有勇气面对困难和挫折，并以积*的心态看待挑战，从中寻找机会和成长。

这三个法则都涉及到领导者的远见、团队合作和个人成长。它们相辅相成，共同构成了一个成功的领导者所需要具备的核心素质和能力。领导者应该通过不断应用和实践这些法则，不断提升自己的领导力，为团队和组织取得更大的成功。

参考资料：

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