Done properly, this is marketing conceived for an audience rather than adapted for it, by people from that audience, with media chosen where the audience actually is. Done badly, it is general-market creative translated and placed in a token buy, which reads as exactly what it is and usually performs worse than doing nothing.
In-culture means made there, not adapted there
A concept developed for the general market and translated carries the references, humour and assumptions of the original audience, and those rarely survive the journey. Ask who develops the creative, what their background is, and whether the concept originated with them or arrived for adaptation. Ask to see work where the strategy differed from the general-market campaign rather than echoing it.
Language is not the same as culture, and neither is one group
Audiences that share a language may differ by country of origin, generation and region, and second-generation audiences often consume in English while responding to culturally specific references. Segment on how people actually behave rather than on a census category. An agency that treats a large population as one audience is offering a stereotype with a media plan attached.
Research has to be primary
Reliable data on these audiences is thinner than on the general market, and the shortfall is usually filled with assumption. Expect the agency to propose primary research: interviews, community partners, testing creative with the actual audience before it runs. That is a real line in the budget and it is what separates this work from guessing in another language.
Targeting by background is legally constrained
Advertising platforms restrict audience targeting on the basis of race, ethnicity and related characteristics, and in regulated sectors such as housing, credit and employment the restrictions are stronger and carry legal exposure. Reach is built through language, interest, media environment and geography instead. An agency that proposes to target on protected characteristics has told you how carefully it reads the rules.
Questions people ask about multicultural marketing firms
Is a specialist firm necessary?
If the audience is a real part of your market, usually yes, because the value is in people who belong to it. A general agency with one bilingual writer is adaptation, not in-culture work.
How should this be measured?
Separately, with its own baseline and its own creative test. Pooled reporting hides whether the work reached the audience at all.
Can we target by ethnicity in advertising?
Generally no. Platforms restrict it and in housing, credit and employment it carries legal exposure. Use language, interest and geography instead.
What does a serious proposal include?
Primary research, in-culture creative development, media chosen where the audience is, and a separate measurement plan.