Some things cannot be taught, they have to be rehearsed. You can read everything ever written about handling a redundancy conversation and still freeze the first time you sit across the table from a real person. Simulation training closes that gap. It is a method, not a venue and not a single product: you build a realistic scenario, put people inside it, and ask them to behave, then debrief and run it again. The behaviour is the point. This page sets out what simulation training is, why it produces change where passive e-learning does not, and how Sidestream designs and measures it. Decision making and problem solving under pressure is the most common brief for it.
What Simulation Training Is
Simulation training puts a person in a situation that behaves like the real one and asks them to act inside it. Three things define it. The scenario has to be realistic enough that people respond as they would at work, not as they would in a classroom. Participants act rather than discuss: they make the call, brief the team, hold the line. And each run is followed by a debrief and a second run, so the learning is built up in layers rather than delivered once.
That second run is what separates a simulation from a demonstration. Ericsson's research on deliberate practice (Peak, 2016) is the reference point: capability grows through repetition with feedback at the edge of what a person can currently do. A scenario run once is an interesting day out. A scenario run, debriefed honestly and run again is how behaviour under pressure changes.
In healthcare and education the same idea goes by other names: simulation learning, simulation-based learning or simulation-based education. Health Education England's National Framework for Simulation-Based Education is one example. Sidestream applies the idea to workplace conversations, decisions and crises, with professional actors playing the people involved.
Why Simulation Training Beats Passive E-Learning
This architecture uses each method for what it does best.
Sidestream's own method description, not a research finding.
The evidence on passive learning is not subtle. Keynotes talking at people, slide decks, video modules, end-of-course questionnaires: they transfer information and they rarely change behaviour. The reason is structural. Knowing what to do and being able to do it under pressure are different capabilities, and only the second one shows up at work. Decisions under pressure: rehearse the moment explains the mechanism: stress narrows working memory, and people fall back on what they have rehearsed.
Donald Kirkpatrick's four-level evaluation framework, updated in Kirkpatrick and Kirkpatrick (2016), makes the distinction measurable. Level 1 is reaction, did people enjoy it. Level 2 is learning, did they acquire the knowledge. Level 3 is behaviour, did they change what they do in real work. Level 4 is results, did that change move an organisational metric. Passive e-learning is genuinely good at Levels 1 and 2. It struggles at Level 3 because it never rehearses the behaviour. Simulation training is built for Level 3 from the start, because rehearsal of the behaviour is the entire method. For the full comparison, see our guide on immersive training versus e-learning, and for the measurement model itself, see what the Kirkpatrick model is. For the AI version of the passive-versus-rehearsed question, see human-led practice beats the AI tutor alone in a 2026 McGill trial.
This is not an argument against e-learning. E-learning is the right tool for knowledge that has to reach a large population quickly and consistently. It is an argument against expecting a video module to produce a behaviour it never asked anyone to practise. The two methods are complementary: e-learning for what to do, simulation training for the capability to do it.
The Three Kinds of Simulation Sidestream Runs
Most of our simulation work falls into three recognisable kinds. The same design principles apply across all three; the difference is the behaviour being rehearsed.
Decision simulations rehearse choices made under time pressure with incomplete information. The participant has to weigh competing pressures, commit, and live with the consequence as the scenario unfolds. This is the kind that suits leadership cohorts facing consequential calls where the theory is well understood but the behaviour under pressure is not.
Conversation simulations rehearse the specific exchanges people avoid or handle badly. The difficult performance conversation, the speak-up moment, the change conversation during a restructure, the feedback that has been deferred for months. A professional actor plays the other person, calibrated to respond exactly as a real colleague would, which is what makes the rehearsal land.
Crisis simulations rehearse behaviour when events escalate and a team has to coordinate under stress. The value is in the conditions: time pressure, imperfect information, and the need to communicate clearly while the situation moves. Teams discover how they actually behave under pressure, which is rarely how they assume they behave.
An Example Simulation
Consider an example two-day decision-under-pressure simulation for a leadership cohort at a 300-person London firm. The brief, in this illustration, is that newly promoted directors make sound decisions individually but freeze in the room when a senior colleague pushes back. The behavioural target is decision-making under live challenge.
Day one opens with a short framing, then straight into the first rehearsal. Each director takes a scripted decision scenario, drawn from the kinds of choice the cohort actually faces, while professional actors play the colleagues applying pressure to keep a weak option alive. The director has to surface the challenge, hold the decision, and explain it. The debrief afterwards covers three things: what the director actually did, what the actors were responding to, and what a stronger version would have looked like. Then the same scenario runs a second time with the adjustment in place.
Day two raises the stakes. The scenarios become less certain, the pushback firmer, and the decisions carry more downstream consequence inside the simulated world. Between the two days, participants try the rehearsed behaviour in a real meeting and bring back what happened. By the close, the cohort has rehearsed the target behaviour several times each, under conditions that approximate the real ones.
In this illustration, success is measured at Kirkpatrick Level 3: whether, three months on, these directors surface and hold decisions under challenge in real meetings, according to the colleagues who sit in those meetings with them. That is the result the design exists to move, and the only one worth putting a number on.
Scope a simulation
Book a free 30-minute consultation. Tell us the decision or crisis you need people to rehearse and we will say whether a simulation is the right format.
Book a Free ConsultationWhy the Scenarios Have to Feel Real
A simulation only works if the participant responds as they would at work, and that depends entirely on realism. Two design choices carry most of the weight.
First, the scenarios are bespoke. A generic case study about a fictional company does not approximate anyone's real operational reality, so the behaviour it produces is not the behaviour that matters. We write the scenarios for the specific cohort, drawn from the context they actually operate in.
Second, the other people in the scenario are professional actors, not fellow participants taking turns. Why that matters, and what a trained actor does that a colleague cannot, is set out on our role-play training page. For a simulation the consequence is simple: the pressure has to be real for the decision to be real.
The Evidence Behind the Method
Simulation training draws on the same research base as the rest of Sidestream's rehearsal work: Kolb's experiential learning cycle, Ericsson's deliberate practice, the Roediger and Karpicke (2006) testing effect, and Edmondson's 1999 work on psychological safety, which is why the debrief has to be a place where people can say what went wrong. What a simulation adds is the scenario itself. Because the decision sits inside events that keep moving, what is retrieved under pressure is judgement, not only a line of conversation.
In a randomised 2020 UCL study by co-founder Ben Laumann (n = 57), rehearsal with a role-play coach produced significantly better feedback delivery than an instructional slideshow or video, rated blind by two independent assessors (the study is summarised on our research page). Its second finding matters for how a simulation is measured: self-rated confidence rose in every group, with no significant difference between them, even though the two passive groups' delivery was rated significantly weaker. That is why Sidestream measures observed behaviour in real work rather than what people report afterwards, so confidence is not mistaken for capability.
How Simulation Training Fits Sidestream's Work
Simulation training is the method. How it is delivered depends on the brief: a focused single-cohort workshop, a multi-cohort programme, or a full immersive production performed for a larger audience. Where the brief is London-specific and venue-led, our immersive simulation training in London page covers the local detail, the venues and the geography. This page is about the method itself, wherever it runs.
Which page is for what: this page covers the multi-stage scenario, where the behaviour being rehearsed is a decision, a briefing or a crisis response and the debrief covers the whole sequence. When the brief is a single exchange between two people, a difficult conversation, a speak-up moment, a conduct issue, the method is role-play training with professional actors, which has its own page. Conversation simulations sit on the boundary: one exchange on its own is role-play; the same exchange as one step in a longer sequence of events is a simulation.
What stays constant across formats is the discipline. Bespoke scenarios, professional actors, an honest debrief, iteration, and measurement at Kirkpatrick Level 3. Everything else flexes to the behaviour you need people to change.
How to Start
Book a free 30-minute consultation at calendly.com/info-sidestream. Tell us the decision, briefing or crisis you need people to rehearse. We will say whether a simulation is the right format for the brief, or whether it belongs in a different method.
More on what we offer, on workshops and training and on immersive events is a click away. Get in touch today. We are Sidestream.
Frequently Asked Questions
What is simulation training?
Simulation training is a method that rehearses real behaviour by placing people inside a realistic scenario and asking them to act, rather than asking them to watch or read about it. At Sidestream the scenarios are performed by professional actors: a difficult conversation, a decision under pressure, a crisis briefing. The participant practises the actual behaviour, gets feedback, and rehearses again. The research base (Kolb, Ericsson, Roediger and Karpicke) is set out in the evidence section above.
How is simulation training different from e-learning?
E-learning delivers content at scale and is well suited to knowledge transfer. It typically produces Kirkpatrick Level 1 (reaction) and Level 2 (learning) outcomes. Simulation training rehearses behaviour and is built to produce Kirkpatrick Level 3 outcomes, observable behaviour change in real work. The two are complementary rather than competing: e-learning teaches what to do, simulation training builds the capability to do it. The UCL evidence for rehearsal over slides and video is on our research page.
What kinds of simulation does Sidestream run?
Three recurring types. Decision simulations rehearse choices made under time pressure with incomplete information. Conversation simulations rehearse the specific exchanges people avoid or handle badly, such as performance conversations, speak-up moments and change conversations. Crisis simulations rehearse behaviour when events escalate and the team has to coordinate under stress. Each type uses bespoke scenarios written for the cohort and performed by professional actors.
How are simulation training outcomes measured?
Against Kirkpatrick Level 3 (observed behaviour in real work) as the minimum standard, and Level 4 (a downstream business or operational metric) where the brief allows. Specific measures include the frequency and quality of the rehearsed behaviour observed by colleagues after the programme, decision-meeting documentation quality, and speak-up rates. The aim is to evidence behaviour change, not satisfaction in the room.
Does simulation training work for senior and specialist teams?
Yes. The method suits any group whose behavioural target is observable and consequential, from emerging managers to executive teams and specialist populations such as clinical leaders and investigating officers. The scenarios and actor casting are calibrated to the cohort's real working context, which is what makes the rehearsal credible for experienced and sceptical participants.
Is simulation training the same as simulation learning?
Broadly, yes. Simulation learning, also called simulation-based learning or simulation-based education, is the name healthcare and education often use. The shared idea is that people learn by acting inside a realistic scenario rather than by being told what to do. Sidestream applies the idea to workplace conversations, decisions and crises: professional actors play the other roles, each run is followed by a debrief and a second run, and the result is measured as observed behaviour at work, Kirkpatrick Level 3.
Simulation Training in Summary
Simulation training is a method, not a venue: you build a realistic scenario, put people inside it and ask them to behave, then debrief and run it again. Because the behaviour is rehearsed rather than described, it produces change where passive e-learning cannot, and Sidestream measures that change at Kirkpatrick Level 3, observed behaviour in real work, not satisfaction in the room.
- Three recurring kinds: decision, conversation and crisis simulations, each written bespoke for the cohort.
- Professional actors hold the other roles, which is what makes the rehearsal feel real enough to transfer.
- Anchored in Kolb, Ericsson deliberate practice and the Roediger and Karpicke testing effect.
- Outcomes evidenced at Kirkpatrick Level 3, with Level 4 where the brief allows.