# Access Rights

There are 5 levels of access rights: model, actions, field, button and record. Every access right is based on the groups of the user. The model and field access rights are checked for every RPC call for which `trytond.rpc.RPC.check_access` is set. The others are always enforced.

## Model Access

They are defined by records of ir.model.access which define for each couple of model and group, the read, write, create and delete permission. If any group of the user has the permission activated, then the user is granted this permission.

## Actions Access

Each action define a list of groups that are allowed to use it. There is a special case for wizard for which the read access on the model is also checked and also the write access if there is no groups linked.

## Field Access

Same as for model access but applied on the field. It uses records of ir.model.field.access.

## Button

For each button of a model the records of ir.model.button define the list of groups that are allowed to call it.

## Button Rule

The ir.model.button could contain a list of rules which define how much different users must click on the button. Each rule must be passed to actually trigger the action. The counter can be reset when another defined button is clicked.

## Record Rule

They are defined by records of ir.rule.group which contains a list of ir.rule domain to which the rule applies. The group are selected by groups or users. The access is granted for a record:

> - if the user is in at least one group that has the permission activated,
> - or if the user is in no group by there is a default group with the permission,
> - or if there is a global group with the permission.