My two cents

There are indeed two ISO standards that can inspire service designers:

1. ISO 23592, Service excellence – Principles and model

2. ISO/TS 24082

Here is how the organisation that created these standards described them in summary when they released them:

“ISO 23592, Service excellence – Principles and model, outlines the terminology, principles and model that make up excellent service. It is complemented by a new technical specification, ISO/TS 24082, which offers guidance on designing excellent service to achieve outstanding customer experiences.” — Source

Buying the two documents with all the details cost about 250$.

The document doesn’t make you certified yet. For that, you have additional expenses: “You can expect an average ISO Certification to cost around $3000-$5000 annually” - source: isoupdate

Other ISO certifications relate to the work service designers do, but they don’t specifically mention Service Design. Here are a few that could interest you:

1. ISO 9001 Quality Management

2. ISO 9241-210

3. ISO 56002:2019 Innovation management

Outside of the ISO certification, there are also certifications that prove the skill level of a service designer. These are certifications that are done by the Service Design Network, and its Academy. There are three level of what they call accreditations for individuals:

1. SDN Accredited Service Design Practitioner costs from €100 to €460

2. SDN Accredited Service Design Professional costs from €360 to €1800

3. SDN Accredited Service Design Master costs from €360 to €1800

And there is one level for organisations called “Service Design Organisation”

If you are interested in a less rigid standard, there are the 15 criteria or principles for Good Service from Lou Downe

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