Most enquiries about autism assessment start with a version of the same question: what does this actually involve? People want to know, before they spend money or time, what they are stepping into. This piece answers that question for anyone considering an adult autism assessment in London with me.
Why adults seek assessment now
The single largest group of new enquiries I see are adults who have spent decades knowing something about how they relate to the world is different, and have only recently started to suspect what it is. Sometimes the trigger is a child being assessed. Sometimes it is a friend's diagnosis. Sometimes it is a moment of acute exhaustion at work that finally makes the masking unsustainable.
A formal assessment offers three things, only one of which is the diagnostic outcome itself. The second is a structured account of how your particular profile shows up: the specific shape of your sensory experience, social processing, executive functioning, and interests. The third is a document that can be useful later: at work, with healthcare providers, in education, in legal contexts, or simply for your own sense-making.
Whether the diagnostic threshold is met or not, most adults who go through a thorough assessment leave with a clearer picture of themselves.
What "neuro-affirming" actually means in practice
The phrase has become common, and like any phrase that has become common it can mean different things to different practitioners. In my practice, neuro-affirming means three concrete commitments.
I do not treat autism as a deficit to be diminished. The criteria in DSM-5-TR and ICD-11 use clinical language, but I read those criteria through a lens that recognises autistic ways of being as valid ways of being. The report I write reflects that.
I do not assess against a stereotype. Adult autism, particularly in adults who have spent a lifetime masking, looks very different from the cartoon version. I look for actual patterns, not the patterns most people associate with the diagnostic label.
I do not pathologise the strategies you have used to get this far. Masking, scripting, special interests as anchoring points, repeated routines that make life manageable: these are noted as the adaptations they are, not as symptoms.[2]
I trained with Marilyn Monteiro, whose strength-based assessment framework underpins the conversational, narrative approach I use rather than a single rigid testing session.[1]
The assessment process, step by step
I conduct the assessment over multiple sessions because a single afternoon does not produce a thorough picture in adults.
Initial consultation. A free ten-minute call where we discuss whether assessment is right for you, what you are hoping to learn, and any specific contexts (work, education, legal) the assessment may need to speak to.
Case history taking session. A longer first appointment to gather your developmental history, current concerns, and self-report. We talk about your earliest memories, school experience, family relationships, current life, and the specific patterns you notice.
MIGDAS-2. The core observational and conversational part of the assessment, conducted across three to four sessions. MIGDAS-2 is a strength-based, neuro-affirming framework that uses authentic conversation rather than task-based testing.[1] Across the sessions we look together at your communication style, sensory experience, patterns of attention, and the interests that anchor you. Spreading the work across multiple sessions rather than condensing it into a single afternoon produces a fuller picture and lets you settle into the conversation rather than perform under one-shot pressure.
MIGDAS-2 informant interview. If you have someone (a parent, partner, sibling, long-standing friend) who knew you in childhood or knows you well now, an informant interview adds context that self-report cannot supply. This is often the part that most clarifies the picture. If no informant is available, I work with that and note it in the report.
Psychological assessment. Standardised measures relevant to your particular questions: cognitive profile, sensory processing, executive function, mental health screening.
Feedback session. Once everything is gathered, I share what I have found, in plain language, and we discuss what it means. There is space for questions, disagreement, and clarification.
Written report. A document you keep, written in neuro-affirming language, containing the assessment outcome, the evidence behind it, contextual recommendations, and resources. It can be shared with employers, the NHS, your GP, or kept private.
The whole process typically takes between four and six weeks of elapsed time.
What you get, and what you do not
You get a thorough, written, neuro-affirming assessment that follows NICE CG142 principles for comprehensive adult autism diagnosis[3] and can be presented as a formal diagnostic report.
You do not get medication. Medication for ADHD, where that is co-occurring, requires a separate prescribing route via a psychiatrist. I work with a reputable and affordable private psychiatrist for that step where it is needed.
You do not get a follow-on therapeutic relationship by default. Some clients move from assessment to therapy with me; many do not. Both are fine. The assessment stands on its own.
Cost and timeline
Assessment fees are £1,500 for autism, £1,350 for ADHD, and £2,500 for combined. Sessions are conducted online via Microsoft Teams, in person at Bayswater or Chancery Lane in central London, or a mix. The report follows once all sessions have completed and the materials are reviewed.
When this is not the right step
Assessment is a substantial undertaking. It is not the right next step for everyone who suspects they may be autistic. It is the right step when you have a specific reason that a formal report would help: work adjustments, study support, healthcare access, family understanding, or your own clarity. If none of those apply and you are simply curious, reading widely from adult-autistic writers and clinicians might serve you better.
Acute distress, crisis, or active risk are not the territory of an autism assessment. The right contacts there are your GP, NHS 111, or the Samaritans on 116 123.
How to start
If you would like to discuss whether assessment is right for you, the next step is a free ten-minute consultation. Neurodevelopmental assessment slots are returning from August 2026.
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