CMO Start Up: What the First 90 Days Require

Starting as a CMO is one of the most commercially exposed positions in business leadership. You inherit a team, a budget, a set of assumptions, and a board that wants results before you have had time to understand what is actually driving them. The first 90 days do not determine whether you succeed, but they almost always determine whether you get the runway to find out.

Most CMO start-up advice focuses on stakeholder management and quick wins. That is not wrong, but it misses the harder part: forming an accurate picture of the business before you start changing it. The CMOs who struggle in year one are rarely the ones who moved too slowly. They are the ones who moved confidently in the wrong direction.

Why the CMO Start-Up Period Is Different From Every Other Leadership Role

Most leadership roles give you a grace period measured in months. The CMO role gives you one measured in weeks, sometimes less. Marketing is visible by nature. The moment you join, people form opinions about your direction based on what they see you prioritising, what you ask about, and what you do not ask about. Silence on a subject is read as either ignorance or intent.

I have seen this from both sides. When I was building out the leadership team at iProspect, we brought in senior marketers who had strong track records elsewhere and watched them spend their first two months trying to replicate what had worked in their previous business. The context was different. The audience was different. The commercial model was different. What worked before was not irrelevant, but it was not transferable without translation.

The CMO start-up period is different because you are simultaneously expected to lead, listen, audit, and deliver. You cannot sequence those neatly. They happen in parallel, which means you need a clear mental framework for what you are trying to learn and by when.

If you are interested in the broader pressures shaping marketing leadership today, the Career and Leadership in Marketing hub covers the structural challenges CMOs face across tenure, board relationships, and organisational design.

Before Day One: What to Resolve Before You Start

The most underused part of a CMO transition is the period between signing and starting. Most people spend it wrapping up their previous role. The better use of that time is getting clear on three things: what the business believes is the growth problem, what the board expects marketing to deliver, and what the current team has already tried.

You will not get full transparency before you start. That is normal. But even partial answers to those three questions will save you from the most common early mistake, which is walking in and diagnosing a problem that the previous CMO already tried to solve and could not.

Ask for access to recent board decks, any existing brand or growth strategy documents, and the last two years of marketing performance data before your first day. Most businesses will share this. If they will not, that tells you something worth knowing about how marketing is treated internally.

Days 1 to 30: Diagnosis Before Direction

The first month should be almost entirely diagnostic. Your job is to understand the business, not to improve it yet. That means structured conversations with every key stakeholder, a careful read of the data, and a deliberate effort to resist the pressure to announce a new direction before you have earned the right to set one.

The conversations that matter most in month one are not with the marketing team. They are with sales, finance, and the CEO. Sales will tell you what marketing is actually delivering versus what the attribution model says it is delivering. Finance will tell you where the budget pressure is coming from and how marketing spend is classified in the P&L. The CEO will tell you what they are worried about that they have not told anyone else yet.

On the data side, the most important thing to audit early is where your marketing spend is concentrated. In my experience, the majority of inherited marketing budgets are weighted toward the bottom of the funnel, capturing people who were already close to buying. That is not a bad thing in isolation, but it creates a ceiling on growth. If you are only reaching people who are already in market, you are not building the future pipeline. You are harvesting the existing one.

I learned this the hard way earlier in my career when I was running performance campaigns for a retail client and convinced myself that the return on ad spend numbers were evidence of marketing working brilliantly. They were not. Much of what we were crediting to performance channels was demand that would have converted anyway through direct or organic. The clothes shop analogy is useful here: someone who has already tried something on is highly likely to buy. Intercepting them at the point of purchase and claiming credit for the sale is not the same as creating a new customer.

Days 30 to 60: Forming a Point of View on the Growth Constraint

By the end of month two, you should be able to articulate the primary growth constraint clearly and in commercial terms. Not in marketing terms. In commercial terms.

The growth constraint is the specific thing that, if removed, would most directly accelerate revenue. It might be awareness among a new customer segment. It might be conversion rate on a specific product line. It might be customer retention in a category where churn is quietly destroying the economics. It might be that the sales team does not trust the leads marketing is generating and so is not working them properly.

Whatever it is, naming it clearly is one of the most valuable things a new CMO can do. It forces alignment. It gives the team a shared problem to solve. And it gives you a basis for prioritising where to focus and what to deprioritise, which is the part of the job most new CMOs find hardest.

During this period, you will also start to get a clearer picture of the team you have inherited. Resist the urge to restructure early. The people in the team know things you do not yet know, and the ones who look like the weakest performers on paper are sometimes the ones carrying the institutional knowledge that holds everything together. Equally, the confident ones who present well are not always the ones doing the work.

When I grew the iProspect team from around 20 people to over 100, the restructuring decisions that worked were the ones made after I understood what each person was actually contributing, not just what their job title suggested they should be contributing. The decisions made on first impressions were the ones I regretted.

Days 60 to 90: Building the Plan and Testing It

Month three is where you start to move from diagnosis to direction. By this point you should have a clear view of the growth constraint, a working hypothesis about what marketing needs to do differently, and enough credibility with the team and the board to begin making the case for change.

The plan you present at the end of 90 days does not need to be final. It needs to be credible. There is a difference. A credible plan shows that you understand the commercial context, that you have a clear hypothesis about what will drive growth, that you have thought about the risks, and that you have a realistic view of what the team can execute. A final plan is a fiction at this stage. Nobody has enough information after 90 days to be certain about anything.

Be honest about what you do not know yet. Boards and CEOs who have worked with good CMOs before will respect that more than false confidence. The ones who expect certainty at 90 days are often the ones who have not worked with strong marketing leadership before, and managing that expectation is itself part of the job.

The Budget Audit: What You Are Inheriting and Why It Matters

One of the most politically sensitive parts of the CMO start-up is the budget audit. Every line in an inherited budget represents a decision someone made, often someone who is still in the building. Challenging it feels like criticism. But not challenging it means you are accountable for spending decisions you did not make and may not agree with.

The approach that works is to frame the audit as a prioritisation exercise, not a performance review. You are not asking whether past decisions were right or wrong. You are asking whether the current allocation is the best use of resource given the growth constraint you have identified. That is a forward-looking question, and it is much easier to have a productive conversation around.

Look specifically at the ratio between brand-building activity and performance activity. Most businesses I have worked with are over-indexed on performance and under-invested in reach. That ratio has usually been driven by pressure to show short-term returns, which is understandable, but it creates compounding problems over time. You cannot harvest demand that you have not first created.

Also look at agency and technology costs as a proportion of total marketing spend. It is not uncommon to find that a meaningful share of the budget is going to tools that are duplicating each other or agencies that are delivering outputs rather than outcomes. Neither is automatically wrong, but both deserve scrutiny.

How to Build Board Credibility Without Losing Marketing Credibility

The tension most CMOs feel in their first year is between speaking the language of the board and maintaining credibility with the marketing team. The board wants commercial outcomes. The team wants marketing leadership. The mistake is treating these as competing demands.

The CMOs who build credibility with both are the ones who translate fluently in both directions. To the board, everything is expressed in commercial terms: revenue impact, pipeline contribution, market share, customer acquisition cost, retention rate. To the team, the commercial goals are translated into clear marketing objectives with measurable outputs. The connection between the two is explicit, not implied.

This sounds straightforward but it requires a level of commercial literacy that not all CMOs have developed. If you have spent most of your career in brand or creative roles, the P&L fluency may need work. If you have spent most of it in performance or analytics, the brand-building side may need attention. The board will test both, often without realising they are doing it.

I judged the Effie Awards for several years, and one of the things that struck me about the entries that won was how clearly they connected creative and brand decisions to commercial outcomes. Not just correlation, but a credible argument for causation. That is the same standard a CMO needs to hold themselves to internally. If you cannot make the argument clearly, the board will fill the gap with scepticism.

The Technology Stack: Assess Before You Invest

Almost every CMO inherits a technology stack that has grown organically and is partially redundant. There will be tools that were bought for a specific campaign and never turned off. There will be platforms that the team uses because they have always used them, not because they are the best available option. And there will be gaps where the team is working around a missing capability using spreadsheets or manual processes.

The temptation is to invest in new technology early as a signal of modernisation. Resist it. Technology decisions made in the first 90 days are almost always premature. You do not yet have enough context to know what the team actually needs versus what they think they need versus what a vendor has convinced them they need.

Spend the first 90 days mapping what exists, what is being used actively, and what the team’s real capability gaps are. Then make technology decisions in the context of the growth plan, not ahead of it. A platform that does not connect to your growth strategy is an overhead, not an asset.

If you are evaluating AI-driven marketing tools as part of your stack review, it is worth understanding where AI is actually adding measurable value versus where it is adding complexity. The Optimizely AI benchmark report offers a grounded view of where AI is genuinely moving the needle in marketing operations, which is a useful reference point when vendors are pitching you on capabilities that may not yet be proven in practice.

What a Strong CMO Start-Up Actually Looks Like

The CMOs who start well share a few consistent characteristics. They ask more questions than they answer in the first month. They are honest about what they do not know. They build commercial credibility with the board before they build creative credibility. They protect the team from reorganisation until they understand what the team is actually doing. And they name the growth constraint clearly and early, which gives everyone a shared problem to solve.

They also do the unglamorous work. Early in my career, when I was told the budget for a new website did not exist, I taught myself to code and built it. That is not a story about resourcefulness in isolation. It is a story about what happens when you take ownership of a problem rather than waiting for permission to solve it. The CMOs who start well have that quality. They do not wait to be given the conditions they need. They work with the conditions they have.

The start-up period is not about proving you are the smartest person in the room. It is about demonstrating that you understand the business well enough to make good decisions on its behalf. That is a more demanding standard, and it takes longer to meet. But it is the only one that matters.

For more on how senior marketers are managing the structural pressures of leadership roles today, the Career and Leadership in Marketing hub covers the full range of challenges facing CMOs at every stage of their tenure.

About the Author

Keith Lacy is a marketing strategist and former agency CEO with 20+ years of experience across agency leadership, performance marketing, and commercial strategy. He writes The Marketing Juice to cut through the noise and share what works.

Frequently Asked Questions