Starting at an MBB firm? Here’s what the first 90 days really look like — onboarding, first project, travel, and building your reputation.
You survived the application gauntlet. You cracked the case interviews. You nailed the behavioral questions. Now you’ve got an offer letter signed and a start date circled on the calendar. Congratulations. The hard part is behind you.
At least, that’s what you think.
Here’s the thing: the first 90 days in consulting are a kind of transition that almost no preparation resource talks about. The internet is overflowing with advice on how to get in. But what happens once you’re actually there? That’s a blind spot. And it catches a lot of new consultants off guard.
This guide is meant to fill that gap with some practical, unfiltered insights about what those early weeks and months actually look like.
Onboarding: Drinking from the Fire Hose
Most top firms invest serious resources in onboarding new hires. It’s exciting. It’s also overwhelming.
Boot Camps and Training Programs
Your first few weeks will probably involve an intensive training program. Depending on the firm, this could be a one-week orientation or a multi-week boot camp that simulates real engagements. You’ll be introduced to proprietary frameworks, internal tools, project management processes, and communication standards, all compressed into a short window.
Don’t put pressure on yourself to master everything right away. The most important skills will get reinforced once you start working on actual projects. Just absorb what you can and keep notes.
Don’t Underestimate Your Cohort
One of the most valuable things about onboarding, and probably the most underappreciated, is the relationships you build with the people who started alongside you. These are the folks who’ll become your sounding boards, practice partners, and emotional support over the next few years. Invest real time in getting to know them. Bonds formed during shared intensity tend to last.
Your First Project Assignment
After onboarding, real consulting begins. Getting staffed on your first project is a milestone that brings excitement and anxiety in roughly equal measure.
How Staffing Works
Different firms handle staffing differently. Some use centralized systems where a coordinator matches you to open projects. Others give you more say in which engagements you pursue. Either way, your first project probably won’t be a perfect fit for your interests or background.
That’s okay. The point of early assignments is to teach you how consulting actually works, not to land you your dream engagement. Approach whatever you get with curiosity and a willingness to learn.
The Learning Curve Is Real
No matter how well you prepared for interviews, the jump from practicing cases to doing real consulting work is steep. Real projects involve ambiguous scopes, messy data, clients with their own agendas, and team dynamics that no case study ever prepared you for. You will feel underprepared. That’s completely normal.
The new consultants who handle this best are the ones who ask questions freely, seek feedback before it’s offered, and resist the temptation to fake competence they haven’t built yet. Your team expects you to be learning. And most senior folks are generous with their time when they see genuine effort and intellectual honesty.
Managing the Intensity
Consulting is demanding. The first 90 days set the tone for how you manage your energy going forward.
Hours and Travel
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Boundaries Aren’t a Bad Word
There’s a natural tension in early consulting between proving yourself and taking care of yourself. The people who manage this well are the ones who communicate openly about workload, flag capacity issues before they become crises, and structure their time with intention.
Setting boundaries doesn’t mean doing less. It means working with enough intentionality that the effort you put in produces the best possible output.
Building Your Reputation
The first 90 days are a critical window for how people start to perceive you. The reputation you build now will influence your project assignments, your access to mentors, and your trajectory within the firm.
Be Reliable First, Brilliant Second
Consistency matters more than occasional flashes of genius. Deliver your work on time. Follow through on everything you commit to. Be someone your team can count on. In consulting, where client deadlines don’t move and coordination is everything, reliability beats brilliance almost every time.
Ask for Feedback (and Then Actually Use It)
Top firms have robust feedback mechanisms. Take advantage of formal review cycles, but don’t just wait for them. Ask your project manager or mentor for quick, informal feedback after key deliverables. Wanting to know how you can improve, and then visibly improving, is one of the fastest ways to build credibility.
Conclusion
The first 90 days in consulting are a period of rapid learning, constant adjustment, and identity formation. Go in with realistic expectations, genuine curiosity, and a commitment to building strong relationships and sustainable habits. The discomfort of those early weeks is temporary. The foundation you build during that time shapes everything that comes after.
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Frequently Asked Questions
What should I prioritize during my first 90 days as a junior consultant?
Your first 90 days should focus on three things: learning internal processes (how projects work, tools, naming conventions), building relationships (meet your team, mentors, and cross-functional partners), and delivering on your first project (do what’s asked reliably and on time). Don’t try to change things or impress with big ideas—establish yourself as dependable and coachable.
How much travel should I expect in my first project?
Travel varies by firm and practice, but expect 30-80% during your first project. This typically means being on-site 3-4 days per week and home for 3-4 days, though some projects require full-week stays. Your team structure and engagement location determine travel intensity—be flexible and view early travel as invaluable for client relationship building and learning.
What’s the best way to build relationships with senior consultants quickly?
Ask thoughtful questions about their decision-making process, volunteer for high-visibility tasks, and show genuine interest in learning. Senior consultants respect people who are curious and execution-focused. Grab coffee with peers and mentors outside your immediate team to build a broader network early.
How do I handle imposter syndrome when starting consulting?
Everyone feels out of place in month one—that’s normal. Your firm hired you because you’re capable of growth. Focus on mastering one skill at a time rather than trying to be perfect at everything immediately. After 60 days, you’ll realize you’ve learned far more than you expected.
What onboarding mistakes should I avoid in my first project?
Don’t over-communicate every small update, don’t skip official training sessions to jump into work, and don’t hesitate to ask for clarification. Avoid criticizing the client’s current state or your team’s processes—you lack context. Respect the hierarchy and chain of command, especially early on.
How do I stay mentally healthy during the travel and work intensity?
Establish routines around sleep, exercise, and social time early. Join office gym groups, find good restaurants near client sites, and maintain friendships outside consulting. The intensity is sustainable when you have outlets and a support network. Use travel days wisely—don’t work constantly.