What is LIMA and its application in horse training?


What is LIMA and what does a LIMA trainer/behaviourist look like?

LIMA which is the acronym for Least Intrusive, Minimally Aversive, has become a popular term in the animal training world following Friedman, 2009’s paper “What's wrong with this picture? Effectiveness is not enough”. In her paper, she proposed a hierarchy to the behaviour change procedures used in animal training, based on previous work in the world of teaching (Alberto and Troutman, 1999) and years of scientific evidence on the effectiveness, benefits, and limitations of training techniques.

The hierarchy (pictured on the right) requires trainers to increase the use of humane techniques and lessen the use of aversive technique; it is a competence criterion that requires trainers to be sufficiently and capable of resolving the majority of training issues by working up to level 4 or below.

“The overwhelming majority of behaviour problems can be prevented or resolved with one or more strategies represented in Levels 1 - 4 (i.e., arranging distant and immediate antecedents, positive reinforcement and differential reinforcement of alternative behaviours). Level 5 (i.e., extinction, negative reinforcement, and negative punishment, in no particular order) may occasionally be the ethical, effective choice under certain circumstances. Level 6, positive punishment (i.e., the application of aversive stimuli that reduces the probability of the behaviour occurring again), is rarely necessary (or suggested by standards of best practice) when one has the requisite knowledge of behaviour change and teaching skills.” (Friedman, 2009)

LIMA also promotes the implementation of behaviour analysts’ standards to animal training and animal behaviour consultancy which can act as a rough checklist for owners when selecting a LIMA professional:


  • Protection of the participants’ welfare at all times.

How to check: Can your LIMA professional give an accurate definition of welfare that is both scientifically and legally sound? Be cautious of professionals that do not mention the 5 freedoms or 5 domains. Does their practice match their words? Does the professional truly understand the welfare implications of utilising level 5 and 6 strategies and does (s)he do everything possible to avoid using them (eg. consult other professionals, use protective contact with aggressive animals, refer your animal to someone more skilled)?

  • Use interventions that are custom-tailored for each individual.

How to check: Be cautious of professionals that have a rigid, fixed training programme or lack flexibility in their reinforcement rates or criteria.

  • Design interventions on the basis of a functional assessment of the problem behaviour.

How to check: Never employ a professional that starts training without asking questions about the horse’s health and the history of unwanted behaviour(s). It is an excellent sign for any professional to ask you about the last time your tack was checked or when your horse has last seen a veterinarian as most behavioural issues are pain related.

Definitions for terms used in the above graphic (Friedman, 2015)

• Antecedent arrangements: The trainer modifies or remove antecedents to make unwanted behaviours or wanted behaviours less/more likely to occur.

• Positive reinforcement (R+): The trainer adds a desired stimulus to increase the frequency of the behaviour.

• Differential reinforcement of alternative behaviours: The trainer reinforces a wanted behaviour using positive reinforcement while removing reinforcement for the unwanted behaviour.

• Extinction: The trainer removes the consequence (operant conditioning) or unpairs the conditioned stimulus with the unconditioned stimulus (classical conditioning) so the unwanted behaviour decreases.

• Negative reinforcement (R-): The trainer removes an aversive (unwanted) stimulus to increase the frequency of the behaviour.
• Negative punishment (P-): The trainer removes a desired stimulus to reduce the frequency of the behaviour.
• Positive punishment (P+) – The trainer adds an unwanted or aversive stimulus to reduce the frequency of the behaviour. 

  • Use only procedures for which there is a scientific basis (evidence-based treatment).

How to check: Can the professional outline the LIMA hierarchy when asked? Does the trainer start by looking at the first two levels? For example, taking the horse's history and suggesting management changes when appropriate? When it comes to training, does the trainer allows the animal to make choices and use food to reinforce behaviour or does (s)he want to confine the animal to a small space (e.g. round pen) or use restraining (e.g. headcollar and lead rope) to utilise higher-level strategies?

  • Use scientific methods to implement and evaluate interventions (e.g., collect pre-intervention baseline data and ongoing treatment data until the intervention is terminated).

How to check: Can the professional give you an evidence-based explanation for each of his/her actions with the animal? Does (s)he apply an evidence-based ethogram to evaluate his/her training and modify his/her intervention accordingly? Can (s)he provide you with the outline for his/her behaviour modification plan if asked and does (s)he modify it accordingly?

Currents issues with LIMA.

Unfortunately, the horse training industry is not regulated. Some trainers may use terms such as “humane”, “force-free” and even LIMA in ways that are incompatible with established definitions in the field. Proof of education (formal or otherwise), participation in CPD and membership to associations is optional and therefore anyone may title themselves as a "horse trainer", "equine behaviourist" or "equine psychologist". Even organisations such as The International Association of Animal Behaviour Consultants (IAABC) who adopt the LIMA approach, accredit equine behaviourists and trainers who do not adhere to LIMA principles by routinely utilising level 5 and above strategies. While LIMA application may slightly differ from one trainer to another as it is competence-based IAABC Code of Ethics Principle III states “In order to ensure best practices, consultants/trainers should pursue and maintain competence in animal behaviour consulting through education, training, or supervised experience, and should not advise on problems outside the recognized boundaries of their competencies and experience.” The pursue and maintenance of LIMA competency is something we are currently lacking in the equestrian industry; an industry where highly aversive and intrusive behaviour-change procedures are socially acceptable, making unnecessary use of negative reinforcement by equine behaviourist seem more humane and less intrusive than it is. It is therefore important for us, horse trainers aspiring to follow LIMA hierarchy to the same standards as other animal trainers to seek out and learn from each other as well as from experts who focus on other species. We must also protect our clients' welfare by promoting correct terminology use in the equestrian community - the main purpose of this article.


  • Friedman, S.G. (2009) What's wrong with this picture? Effectiveness is not enough. J. Appl. Comp. Anim. Behav [online]. 3, pp. 41-45.

  • APDT (2017) Position Statement on LIMA: What Do you Want the Animal TO do? Accessible at: HERE