What causes it?
We don't really know yet. Scientists have been working for years to try and find out whether there is a cause and whether there is a cure. One thing that is agreed is that the problem is highly complicated.
Stammering is probably not caused by one single thing for a person - it is more likely that it is the result of very many factors. More importantly, the ingredients of stammering are probably different for every person who has a stammer. And the things that help stammering may be slightly different for everyone too.
This diagram shows the four different areas which may influence your stammer, some of which may apply to you.
How can I get help?