Do You Still Need a Marketing Plan? Yes, But Constant Updating Is Key. Adjust the time frame to be more agile to respond to change on the ground (or on the web).

Today's marketers face a different challenge than did their predecessors of just a decade ago. The constant rise and fall of new online networks of people and platforms, from MySpace to WhatsApp, has changed the way companies find, connect with and acquire new customers.

Real-time marketing has involved companies demonstrating quick response to public events (think Oreo's tweet about last year's Super Bowl power outage). Today, effective digital marketing is typified by use of rapid A/B testing, iterating and optimizing on ideas and campaigns and aggressively scaling the tested strategies that prove most promising. This more scientific approach has been formulated by forward-thinking online marketers under the pressure of managing constant change.

In today's fast-paced world the old marketing plan is antiquated. While planning is still important, it needs to evolve into a more iterative and nimble process.

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Agile contemporary marketers know there's a good chance that conditions will be different next month. Unlike marketers a decade ago, they have better visibility about which programs succeed and which fail. Successful campaigns can be doubled down on, shifting resources from poor performers to maximize growth. This newfound dexterity is the key to their success.

Since marketers have adapted, why haven't most marketing budgets and plans?

In a world of constant adjustment and real-time performance feedback, long-term plans and fixed budgets are becoming increasingly unrealistic. It's enough to make someone wonder whether marketing plans are even relevant anymore. Yet implementing a marketing program without any sort of plan or strategy seems not only unwise but flat out reckless.

So what does an agile marketing plan of today look like? I asked this very questions of the community at the site I started, Growthhackers.com, where marketers share ideas and best practices, and participants in the conversation had a lot of interesting insights, which I've synthesized below:

1. The stage and size of the company matters.

Startups and Fortune 500 firms have very different priorities and challenges. By definition their planning needs are different. For startups, being noticed and acquiring new users trumps devoting hours to developing a long-term vision. Large brands have a different challenge: Finding initiatives that will create meaningful growth is key, and these big bets require more planning to protect the company from big losses. The first step in creating a more nimble planning process is to right size it for the company's stage. There is no one-size-fits-all marketing plan.

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2. Agile companies need agile plans.

For startups and perhaps all companies, the 50-page Powerpoint marketing presentation is a relic. Shorter feedback loops necessitate shorter-term, more focused planning. Companies that try to create year-long plans and budgets lock themselves into a structure that won't allow them to capitalize on rapidly emerging opportunities or cut campaigns that are clearly losing money.

Big companies can miss out without flexibility built into their planning and execution.

Rather than formulating one- or two-year plans, many companies now choose to create three- or six-month road maps that are designed to target the next business milestone as quickly as possible. In one such short-term plan, the goal might be to focus on validating a new market segment or completing a series of tests for ways to better attract and convert more consumers into buyers.

Once those growth hypotheses are proved (or disproved) over the course of a few months, the next stage of a plan might focus on expanding deeper into the market, testing ways to acquire customers in an adjunct segment or retention strategies to handle new customers.

3. Design a plan that's cohesive, with adequate vision.

During a time of constant change, keeping everyone in an organization on the same page is a challenge. Moving fast can throw even the closest knit of groups out of sync -- particularly when staffers work across a large organization. Even as the day-to-day operational reins are loosened so teams can capitalize on short-lived opportunities, everyone must row in the same direction.

Yet the plan still needs to keep everyone aligned with a vision for the company: What the company is -- its branding, positioning, target markets, competitor analysis and product information -- must be clear. Set the growth goals, major initiatives for achieving them, which key performance indicators will be used and the resources required. The plan should also express the company's knowledge about what's worked and why.

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4. Be open to change and iteration.

Marketing plans should be created in a format so staffers can provide feedback and learning based on a campaign's performance and suggest new opportunities for driving growth. Rather than a Powerpoint etched in stone, agile plans must be living documents that are constantly referenced and updated. With team members contributing real-time data, this document can serve not just as a plan but a nerve center for the marketing organization to keep tabs on what's working.

A plan that's continually updated, packed with relevant test and program results, is not only more relevant. It's also more effective for driving growth, keeping staffers aligned and ensuring that opportunities are capitalized upon. Business owners can then allocate resources not according to annual budgets but on performance, putting more wood behind their most potent arrows and deftly making adjustments when conditions change. Keep planning docs on a company intranet or wiki that can be updated and commented on, or use Google Docs for smaller teams.

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5. Collaborate across departments.

Today's companies that are growing fastest haven't done so with traditional marketing campaigns. It's been the products themselves that generate the growth. While marketers previously weren't involved in product decisions, tighter collaboration is needed across departments. Product, engineering and marketing need to work together to create sustainable growth.

In researching successful companies, Morgan Brown and I repeatedly found that removing barriers between teams is essential for finding new growth opportunities. For the 10 companies we profiled in our book, Startup Growth Engines, agility came through coordination throughout a company, with every department involved in and invested in driving growth. Plans need to account for growth everywhere, not just at the marketing campaign level.

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