The right of substitution, where applicable, may be exercised by criminal and juvenile defendants and all parties in a civil action.
Substitution for cause can be for any bias a judge may have in the case, such as an association with a party (family, friendship or even stock ownership), having made vocal comments in the past on the topic at trial, etc.
The right of substitution with cause does not have a limitation on the number of times it may be called for, such that parties may exercise the right until they find a neutral judge.
However many jurisdictions require the right be exercised within a certain time after the bias has been discovered by a party or else the right will be waived, often 30–60 days.
In criminal or juvenile courts the right may be exercised after arraignment or indictment but before a preliminary hearing.