When Should a Police Officer Inform Me of My Rights?

I have a lot of clients who tell me that an officer waited to read them their "rights" until a long time after an arrest.  The "rights" that they are talking about are referred to as "Miranda rights" based upon a US Supreme Court case called Miranda versus Arizona.  These rights are well known to many people because we hear them on every cop show on T.V.:  "You have the right to remain silent.  Anything you say can and will be used against you in a court of law.  You have the right to attorney prior to questioning.  If you can't afford an attorney than one will be provided for you." 
These rights only apply to questioning by the police while IN CUSTODY.  They generally do not apply to pre-custody questioning such as when a cop comes to the a scene to investigate and is asking questions trying to figure out who did what.  "In custody" does not necessarily mean in handcuffs or at the police station.  It could be somewhere else.  The test of whether someone is "in custody" is based upon the particular circumstances and whether that person was free to leave.  A person only has to be notified of these rights just prior to the questioning, not at the time of the arrest.