Entry with a Schengen visa
Schengen visas (Visa Category C) can be issued for short-term stays of up to 90 days in countries in the Schengen area, e.g. for visits, tourism or business purposes, or medical treatment.
The consulates of the signatory countries of the Schengen Agreement are responsible for issuing Schengen visas.
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Economic activity
As a rule, you are not permitted to work with a Schengen visa.
Otherwise, your visa states whether and to what extent you are permitted to work.
If the C-Visa explicitly states that work or Business is allowed in the Remarks area then you can, otherwise you cannot do so.
Application for Schengen Visa (Link to Application Form Pdf for Germany)
- Hauptzweck(e) der Reise / Main purpose(s) of the journey:
- Geschäftsreise / Business
When checking Geschäftsreise / Business then
- GESCHÄFTSVISUM will be added to the REMARKS field of the C-Visa (as seen in the second Image below).
Multiple purposes can be selected, each one being added to REMARKS.
Each country does this differently:
Annex 22 1 National entries in the "comments" section of the visa sticker
For the sample Business (not all countries have this category)
- BENELUX (Belgium, Netherlands and Luxembourg)
- BNL 13 : visa issued for "business purposes".
- CZECH REPUBLIC
- C/VF/01/-/--; multiple-entry visa for up to 90 days – commercial
- Hungry
- Italy
- Latvia
- Malta
- Poland
- Slovenia
- Slovakia
- obchodná cesta (business trip)
- Spain
- Sweden
- "Affärsanledning": Business
- Switzerland
Standard C-Visa issued for the whole Schengen Area

This one says Visitor Visa - Working not permitted
- this is the new sticker type visa
A Business C-Visa must be explicitly applied for and the application must include
- Company covering letter with entire travel plan (itineary)
- Invitation letter from the business partner

This one says Visiting-/Business Visa - Working not permitted
What you will need is a short term D-Visa that allows you
- to work (training is considered work) for a specific period
- at a specific firm in a specific country

This one says Student Visa for Uni X - Working permitted according to bla bla bla...
- notice also that it is only valid for a specific country and a date from/to
- valid for other Schengen Countries vists where the 90/180 days rule applies
A D-Visa is a national visa for a specific purpose and should not conflict with an existing long term C-Visa that serves a completely different purpose.