Waterfall and Agile are often depicted as rivals: an old-guard project management methodology competing with a nimble newcomer. 从本质上讲，它们之间的区别在于可预测性和适应性. 瀑布法通过在一开始就预先确定功能，并认为只有在这些功能完全实现后项目才会完成，从而争取可预测的结果. Agile promises adaptability, delivering a minimum viable product (MVP)，然后迭代地发布新功能并收集用户反馈来指导改进的路径.

Despite the oppositional narrative, 瀑布式和敏捷通常在组织中同时存在. In 2021, the Project Management Institute 报告说，信息技术和金融行业是敏捷的主要采用者. Even so, Waterfall remains prevalent, 在这两个行业中，几乎有四分之一的项目采用了混合方法, according to the PMI survey.

Since its official introduction by software developers in 2001, Agile has continued to grow in popularity, 甚至悄悄进入了瀑布方法仍然占主导地位的建筑和能源等行业. A hybrid approach 以提高效率为目标，将两种不同的管理框架或系统的各个方面结合起来. In this article, 在不同行业中从事过敏捷-瀑布混合项目的项目管理专家反思了混合项目管理的挑战和好处.

What Is an Agile-Waterfall Hybrid?

“真正的混合是预测和不确定工作的结合，”他说 Jim Stewart, a Boston-area Toptal project manager, Scrum master, Agile coach, and consultant. In a hybrid model, Waterfall provides the overall structure for the well-understood, predictive aspects of the project, and Agile techniques are used for the iterative, more uncertain parts.

In this way, 一个公司可以用敏捷的方式创建软件，但在推出过程中遵循瀑布的方法. 一家金融公司可能会开发一种产品，其主要功能在发布前必须经过审核和批准. Still, 这些特性的较小部分可以由开发团队通过一系列的sprint进行迭代, as can other aspects of the user interface.

当决定如何在瀑布环境中实现敏捷时，灵活性是关键. “I don’t believe in … one-size-fits-all,” says Miroslav Anicin, a project manager based in Belgrade, Serbia. “You can’t … apply methodologies by the book. 您需要确切地知道如何根据团队成熟度等不同因素来调整这些方法, company culture, subject cultures, the type of project, the size of the team, and the size of the product.”

Why Use a Hybrid System?

敏捷已被证明比传统方法更具适应性和效率. 大型跨国公司的高管们普遍同意这一点 Agile is necessary for achieving strategic aims. 所以你可能会想:为什么组织要继续使用Waterfall?

Risk management 是阻碍组织走向纯敏捷的常见障碍，尤其是在高度敏捷领域 regulated industries 在这种情况下，项目需要外部组织的批准，需要文件和严格的时间表. Because risk analysis must occur before project planning in these industries, 不断变化的分析要素将需要新一轮的规划. “我曾在一家经营临床试验的公司工作，(这个领域的)审计非常疯狂，”他说 Juan Vilmaux, a project manager based in Córdoba, Argentina. “你必须经历几个由FDA等外部机构定义的过程. If you work in Agile, 您不断调整您的范围或待办事项(重新确定优先级)，这可能会干扰这些审计.”

Toptal project manager David Machiels, based in Brussels, Belgium, 请注意，要求隐私保护的项目需要谨慎地定时发布. 他领导了一个混合团队开发身份管理平台 Microsoft Azure Active Directory for a European banking group. His team used Agile on some development steps, 但因为银行出于对数据隐私的担忧，不愿意将信息放到云端, they provisioned the system on a local server. 然后，团队遵循了一个清晰的瀑布式操作顺序. “首先，你需要完成内部部署，”他说. “You also need the cloud implementation to be done. Then you can start doing the connection between the two.”

当敏捷被混合到瀑布环境中时，大型项目可以被分解成史诗和史诗 user stories for more flexible development. Then completed features can be released on longer time frames. “Sometimes you have what I call a big bang delivery,” says Grant Schuleman, a Toptal project manager in Johannesburg, South Africa, who has worked in financial services, banking, and stock exchanges. He describes how a team would deploy incrementally to a user acceptance testing (UAT) environment. 一旦在UAT中签署了所有特性，产品就会在一个大型部署中发布. 他说:“这可能需要一年的时间，具体取决于项目的规模。.

On his largest program, Schuleman有120个人在10个项目中工作，其中一些人在Waterfall工作, some in Scrum, and some hybrid. He also ran a scrum of scrums 每隔一周，以确保较小的团队为下一系列的冲刺和互补的速度工作. 不同方法的编排引入了灵活性，同时仍然适应组织的需求，这阻碍了他们走向完全敏捷.

The Hardest Part of Going Hybrid

敏捷-瀑布混合模式的成功取决于项目经理如何定制给定情况下的过程. 项目经理必须为产品找到正确的方法组合, team, and end users—yet hybridization seldom follows a preset formula.

通常，决定敏捷能否成功地融入现有瀑布系统的最重要因素是团队成员和其他涉众的认可程度. A team must be open to change and excited to try new things. If team members aren’t well-versed in the new process, or only think of Agile as a buzzword, they might not see a reason for change. Project managers eager to combine Waterfall and Agile must foster understanding 并鼓励团队和组织考虑产生最佳结果的方法.

当Schuleman试图将敏捷过程集成到遗留应用程序的更新中时, for example, he found that the experiment wasn’t embraced by the developers, 他们已经习惯了在Waterfall中工作，并且不理解为什么工作被分成史诗和用户故事. Team members wanted to work on everything at once. Based on that resistance and other factors, he realized a hybrid approach wasn’t appropriate, nimbly changed course midway, and guided the team to complete the project using pure Waterfall.

Vilmaux has had similar experiences working on projects, especially those with risk management considerations. 有时候，混合会增加你失败的几率，“因为你得到了两个世界中最糟糕的部分。. 你限制了敏捷，但敏捷的本质是拥抱变化和灵活. You start losing all of that … within a Waterfall environment, 哪一种在线性模式下(固定和确定)效果最好?在这种模式下，改变并非不可能，但代价可能非常高昂. 在加入敏捷的过程中，你开始在瀑布世界中推进非线性的东西.”

In Schuleman’s and Vilmaux’s experiences, 希望遵循混合软件开发方法的项目经理需要这样做 coach their teams through new concepts. 然而，他们也必须愿意承认这种杂交 isn’t working and adapt appropriately.

考虑到这些因素，即使在规避风险的环境中，混合动力车也能取得成功. Anicin最近为国际金融公司(世界银行集团的一个成员)在波斯尼亚和黑塞哥维那领导了一个成功的混合项目. The plan-driven project followed highly detailed requirements 和规范，并涉及许多组织和政府利益相关者. Yet the teams worked in Agile from the beginning, 客户最终以更快的时间以更低的成本获得了更好的产品. Anicin says, “It was hard, but it worked.”

Using Agile Hybrid As an Upgrade

As industries continue to undergo digital transformation, more companies are becoming curious about Agile. Even if a company isn’t ready to dive right in, a gradual introduction to Agile can pay dividends over time. 一个主要原因是敏捷适应不确定性，这是任何项目的特征.

Agile also offers transparency. “I prefer Agile because I can see the changes,” Schuleman says. “With Waterfall, there can be a lot of smoke and mirrors: ‘We’re 20% complete,’ ‘We’re 30% complete,’ but then you’re stuck on 80% for another eight months. It’s far easier to hide problems. With Agile, you’re having daily scrums, 如果一个用户故事被搁置了很长时间, it’s easy to say, ‘This thing’s not moving; what’s the problem?’”

Incorporating Agile slowly into Waterfall can provide advantages, 特别是当瀑布式思维方式的某些方面目前适用于团队时. 例如，瀑布法在发现和计划阶段就能发挥出色. “When we are talking about the blended approach, we are providing a much more detailed product backlog,” Anicin says. In a hybrid project, he uses this backlog to give his team a more detailed, 瀑布式的对成品长期期望的看法. 然后，他将自己的团队“融入到产品中，而不仅仅是项目中，”他说. “我希望整个团队都能了解产品细节，因为他们需要这些 product ownership, which is so important.”

A company and team might not be ready to go pure Agile, but at the very least, 项目经理可以从增加敏捷实践和缩短敏捷实践中获得可观的收益, more frequent delivery deadlines. If a project manager is rigorous, smart, and careful about implementation, 敏捷-瀑布混合方法可能正是组织升级项目所需要的.

本文最近进行了全面的更新和重写，以纳入最新和最准确的信息. 我们要感谢格雷格·奥布莱恩对原文的贡献. Please note: Comments below may predate this update.