It sets out six strategic principles, being: (page 5)

- Detention in Police Custody is safe and used only when necessary, not punitively; 

- Custody supports effective investigation of crime and adds value to the criminal justice system;

- The custody experience is non-discriminatory and transparent;

- Custody practitioners are professionals in their field, trained to a national minimum standard and accountable;

- Custody practice is ethical and evolves, reflective of changing demands, best practice, learning from previous failings;

- Engagement with partners is effective and efficient in the support of the investigation of crime.

Matters of particular interest for practitioners that the National Strategy states are:

- The primary purpose of custody is for the purpose of investigation. Detention must be necessary. It must never be for ease of operation, convenience or punishment: page 3.

- Detention in police custody due to lack of alternative provision by local authorities or health care provides should be minimised: page 3.

- Police custody is not always the appropriate response, for example, for children or vulnerable people: page 4. 

- Custody should be used for children only as a last resort: page 7.

- The use of police custody for Mental Health Act detentions should be eliminated: page 7.

- The incidents and length of pre-charge bail should be reduced: page 9.

 The full strategy is available on the NPCC website, here