SEM
Aussi : SEM, Search Engine Marketing, search marketing, marketing sur les moteurs de recherche
Search Engine Marketing: reaching audiences through search engines, combining organic SEO and paid search (SEA) to capture user intent at the moment of search.
What it is
SEM (Search Engine Marketing) is the discipline of driving visibility and traffic from search engines such as Google, Bing, and others. It is an umbrella term that covers two complementary channels:
- SEO (Search Engine Optimization): earning organic (unpaid) rankings by improving content, technical health, and authority.
- SEA (Search Engine Advertising): buying paid placements, typically through auction based, pay per click (PPC) ads keyed to search queries.
Both channels target the same asset: the search results page. What differs is how you appear there (earned versus paid) and how you pay (effort and time versus per click bidding).
Why it matters
Search captures active intent. A user typing a query is often close to a decision, which makes SEM one of the highest converting acquisition channels.
- Reach at the point of demand: you meet people who are already looking.
- Measurability: clicks, impressions, and conversions are trackable end to end.
- Budget control: SEA can be scaled up or paused quickly; SEO builds a durable, lower marginal cost asset.
How it is used in practice
A typical SEM program balances the two channels:
- Keyword research: identify queries by volume, intent, and competition.
- SEO work: technical fixes (speed, crawlability), content, and backlinks.
- SEA work: campaign structure, ad copy, bidding strategy, and landing pages.
- Measurement: track CTR (click through rate), CPC (cost per click), conversion rate, and ROAS (return on ad spend).
Common metrics to steer decisions:
- Quality Score: relevance signal that lowers paid costs.
- CAC (customer acquisition cost): blended cost across channels.
- Impression share: how often you appear versus the addressable total.
Worked example
An executive education platform sells a CFO track. The query "finance training for executives" has strong intent.
- SEA: they bid on the keyword. CPC is 4 euros, CTR is 5 percent, landing page converts at 3 percent to a lead. To get 30 leads they need 1,000 clicks, costing 4,000 euros, so cost per lead is roughly 133 euros.
- SEO: in parallel they publish a comparison guide that, after four months, ranks organically and delivers 20 leads per month at near zero marginal cost.
The lesson: SEA buys immediate, controllable volume; SEO compounds into cheaper traffic over time. Mature teams run both and reallocate budget based on measured cost per acquisition.