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How to apply impact mapping to software with examples

Impact mapping can reduce scope creep and enable flexibility in the SDLC by creating a shared understanding among all stakeholders. Learn how to apply it to software projects.

Impact mapping is a planning technique that starts with goals, communicates assumptions and aligns the activities of software development teams with business objectives. When properly applied, this leads to better decision-making.

By focusing on business goals throughout the process, impact mapping differs from user story mapping and other tools commonly used in strategy planning and requirements development. Impact mapping can be employed in any strategic development effort, but it fits software projects so well because of that built-in focus on the business goal, which enables agility and change, while also limiting scope creep.

The flexibility of impact mapping makes it possible to adjust processes in response to changes in the competitive landscape without a loss of focus. Focusing on the goal helps to reduce the chance that a project expands beyond the original scope or is overengineered.

As impact mapping is a powerful planning tool, it is critical to use it early in the SDLC. The software project manager should include all business stakeholders and representatives from the development, testing and UX teams. Impact mapping is most effective when project teams employ it as a visual technique. Teams usually document the planning tool as a mind map, although a table format also works.

How to create an impact map

Gojko Adzic, who explored and documented this technique in his book, Impact Mapping: Making a Big Impact with Software Products and Projects, uses four questions to facilitate the development of an impact map: why, who, how and what. The answers to these questions translate into four corresponding elements: the goal, the actors, the impact and the deliverables.

Why

The why -- or the goal -- is put in the center of the map. The business and software development teams focus on the why throughout the project. This helps them understand the importance of adjustments to meet changes in customer needs and the competitive environment. Clearly defining the goal helps the business and technology teams align expectations. Goals should be focused on a problem, not a solution. They should be SMART -- i.e., specific, measurable, action-oriented, realistic and timely. Testers can play a significant role in defining the goal by asking questions that remove ambiguity.

Impact mapping can be employed in any strategic development effort, but it fits software projects so well because of that built-in focus on the business goal, which enables agility and change, while also limiting scope creep.

Who

The who describes the actors who can influence the outcome of the goal. The who isn't limited to the customers or users; it includes anyone who can facilitate or hinder the accomplishment of the goal. Remember to include all influencers -- these can be internal as well as external. Don't forget to include stakeholders as well. Think about how regulatory agencies and integrations with banks and digital wallets might affect not only the product, but also the development process. Be as specific as possible when defining the actors. For example, not all users have the same wants and needs, so it is important to understand the effect that each user has the potential to make.

How

The how pertains to the impact element. It defines how each of the actors affects the goal and considers the actions actors should take or not take. This enables developers to identify and focus on the most critical tasks. In documenting the impacts, it is important to describe specifically how behaviors need to change rather than just the actions actors will take. Include behaviors that should not change. These translate into the negative test cases, so testers can be especially helpful in identifying them. Address both positive and negative impacts. Recognizing a potential negative impact early creates more time for risk mitigation.

What

The what question describes the scope in terms of potential deliverables. It outlines the features that are needed to enable and, in some cases, discourage the behaviors that create the impact. This is the time to be creative and consider the unexpected. Product managers can always detail and prioritize the deliverables later.

Impact map examples

To illustrate all this, consider this example impact map template for a subscription box company. This organization wants to increase sales by prompting customers to purchase add-ons to their boxes each quarter. Currently, stylists choose initial selections and offer suggested add-ons. Customers also have the option to select items to add to their box.

Here is how that looks in a table format. Representing an impact map this way puts more emphasis on the category that each component of the impact map falls into.

Goal Actors Impacts Deliverables
Increase revenue from add-ons by 25% Current customers Accept add-ons selected by stylists Waive styling fee when add-ons are selected
Choose additional add-ons Offer additional discounts for selecting add-ons
New customers Select a subscription that includes add-ons Add new subscription plan that includes add-ons
Choose additional add-ons Offer extra discounts for selecting additional add-ons
Stylists Suggest add-ons Add SMS/email functionality to communicate with customers
Promote add-on sales Additional commission on add-ons

Here is the same example represented in the mind map format. In this format, the decisions flow from the overall goal through to the actors, impacts and, finally, individual deliverables. It shows more explicitly how each decision contributes to the goal.

A mind map showing impact mapping for a fictional subscription box company

Gerie Owen is a lead quality engineer. She is a conference presenter and author on technology and testing topics, as well as a certified Scrum master.

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