Obsessive-Compulsive Disorder (OCD) involves a pattern of unwanted, intrusive thoughts, images, or urges known as obsessions that create significant anxiety or distress. In response, a person may feel driven to engage in repetitive behaviors or mental acts, called compulsions, in an attempt to reduce that distress or prevent something bad from happening. While compulsions may provide short-term relief, they ultimately reinforce the cycle of OCD by strengthening the connection between the obsession and the need to neutralize it. Over time, this makes the obsessions feel more frequent, more believable, and more urgent, keeping the disorder going.
When I’m working with a client with Obsessive Compulsive disorder (OCD), one of the first things I do is try and provide a clear understanding of what OCD is and how it operates.  I try and make it clear that OCD thrives when a person uses reassurance strategies.  For example, if a client comes to me with a concern that they might lose control and end up harming a loved one, (often known as harm OCD), such as with a child or spouse, but has no history of doing so,  I might feel inclined to provide the client with reassurance that the likelihood of them doing so is very low.  This approach however well intentioned might create more long term problem for the sufferer as we will discuss in more depth.
Using the example of someone experiencing intrusive thoughts about losing control and harming a loved one, it can be helpful to look at what a typical OCD pattern might involve.

First, the person notices an intrusive thought, for example, an image or urge related to harming their child or partner. This thought is unwanted and distressing, and it often leads to a sharp spike in anxiety. They may begin to question what the thought means: “Why am I thinking this?” or “Does this say something about who I am or what I’m capable of?”

In response to this anxiety, the person feels driven to do something to reduce the distress or gain certainty. This is where compulsions come in. They might try to suppress or block the thought, avoid being alone with the person they fear harming, mentally review their past behavior for reassurance, or seek reassurance from others.

These strategies often work in the short term. The anxiety decreases, and the person feels some relief. However, this relief is temporary. Because the compulsion “worked,” the brain learns that the intrusive thought is important and potentially dangerous, and that it must be managed or neutralized. As a result, the thought tends to return more frequently and with greater intensity.

Over time, this creates a self-reinforcing cycle: the more the person tries to control or eliminate the thought, the more persistent and distressing it becomes. The problem is not the presence of the thought itself, but the pattern of responding to it. Breaking this cycle involves learning to experience the thought without engaging in compulsions—even though this can feel counterintuitive at first.

I try and help the client to adopt the attitude that they can learn to live with uncertainty (ex. maybe they really are a threat to their loved ones or maybe they will be infected with some disease if they don’t wash their hands excessively) because as uncomfortable and scary as it is, this provides the best long term treatment and symptom relief for the disorder.   I am more inclined then to remind the client, especially if they are looking for reassurance, that providing them with reassurance is not likely to help with their OCD,  but that accepting some uncertainty about their fears is. While it might be true that most OCD sufferers are not likely to act on their obsessive fears, it is probably not a good idea to overly emphasize this fact.  The goal here is to help sufferers to learn to accept and live uncertainty,  much like the general population does.
In fact, it is well established in the psychological literature on Obsessive-Compulsive Disorder (OCD) that most people experience random, intrusive thoughts from time to time. Thoughts about causing harm, acting out of character, or doing something inappropriate can occur in the general population without leading to distress or concern.

The key difference for someone struggling with OCD is not the presence of these thoughts, but how they are interpreted and responded to. Individuals with OCD are more likely to assign significant meaning to these thoughts—questioning what they say about their character, intentions, or potential for action. This heightened sense of importance can make the thoughts feel threatening and urgent, which in turn fuels anxiety.

In this way, it is not simply the thought itself that creates the problem, but the relationship the person has with the thought. When a thought is treated as meaningful or dangerous, it demands attention and response. Conversely, when thoughts are recognized as mental events—essentially “just thoughts”—they tend to pass more naturally without escalating into distress.

An important part of treatment, therefore, involves learning to relate to intrusive thoughts differently: noticing them without assigning undue significance, and allowing them to come and go without engaging in efforts to analyze, suppress, or neutralize them.