Plain-language explanation.
Applied Behaviour Analysis (ABA) applies behavioural principles to change behaviour in socially significant ways, grounded in Skinner's operant conditioning research, widely used to support autism, developmental disabilities, and learning difficulties.
Core concepts and standard treatment.
Core ABA covers the three-term contingency (antecedent — behaviour — consequence — ABC model; discriminative stimulus — Sd; motivating operations — establishing and abolishing; behaviour topography — frequency, duration, latency, magnitude), reinforcement and punishment (positive/negative reinforcement; positive/negative punishment; differential reinforcement — DRI, DRO, DRA, DRL; extinction — extinction burst; schedules of reinforcement — CRF, FR, VR, FI, VI — variable ratio most resistant to extinction), measurement (event recording; duration; latency; interval recording — whole, partial, momentary; IOA — inter-observer agreement — kappa; permanent product; ABC recording), and functional behaviour assessment (FBA — function of behaviour — attention, escape, tangible, sensory; indirect — FAST, MAS, QABF; experimental functional analysis — Iwata — control vs test conditions; IISCA — Hanley).
Deeper theory, debates and edge cases.
Advanced ABA covers verbal behaviour (Skinner Verbal Behavior 1957 — mand, tact, echoic, intraverbal, autoclitic; VB-MAPP — Sundberg — language assessment for autism; ABLLS-R; mand training — first verbal operant; MO-based teaching), skill acquisition (DTT — Lovaas — mass trials; NET — natural environment teaching — incidental teaching; errorless teaching — most-to-least prompting; transfer of stimulus control — prompt fading; task analysis — chaining; video modelling; PECS — Bondy and Frost), and ethics and regulation (BACB — BCBA, BCaBA, RBT — ethics code; PBS Alliance restrictive practice reduction — RIDDOR; safeguarding; controversy — aversives — Judge Rotenberg Center — UN CAT; neurodiversity critique of ABA — ASAN autistic self-advocacy; NICE NG11 — autism — behavioural approaches within multimodal support).
How it is applied in practice.
At the BCBA and behaviour analyst service manager level, practitioners contribute to Journal of Applied Behavior Analysis; lead autism intervention services (Lovaas Institute; NAS ABA schools — Treehouse CABAS; NHS CAMHS behavioural approaches; EIBI — Early Intensive Behavioural Intervention); design OBM systems (behaviour-based safety — Aubrey Daniels International; performance feedback in healthcare; reinforcement of job-based outcomes in nursing); advise on PBS in adult services (BILD PBS Academy; CQC PBS inspection framework; STOMP — stopping over-medication of people with LD, autism, mental health; NHS England reducing restrictive practice programme — RRP); and lead single-case research (SCED — AB, ABAB, multiple baseline, alternating treatments designs — What Works Clearinghouse SCED standards — Kratochwill; BACB evidence standards).