Speech and Language Impairment


Children with speech and language impairment or speech, language and communication needs (SLCN) find it difficult to communicate with others.  Speech refers to the ability to articulate the sounds that make up language (eg ‘b’, ‘w’, ‘sh’) clearly. Language is about understanding and using words to make sentences and bigger chunks of language. Communication refers to the appropriate use of language and nonverbal aspects to help interaction between people.

Children with SLCN form one of the largest groups of those with special educational needs  (SEN), as SLCN is associated with several other types of SEN, eg hearing impairment.

Specific language impairment or SLI is a type of SLCN. Children with SLI are able and healthy as other children, but they have difficulty talking and understanding language. SLI is also known as primary speech and/or language impairment.

If children have SLCN as a result of another condition such as learning difficulty or physical problems such as hearing loss (see entry Deafness), this is known as secondary speech and/or language impairment.


Medical text written November 2012 by Professor Geoff Lindsay. Last updated April 2016, by Professor Geoff Lindsay, Director, Centre for Educational Development, Appraisal and Research (CEDAR) University of Warwick, Coventry, UK.

What are the symptoms

A child with speech, language and communication needs (SLCN) may:

  • have speech that is difficult to understand
  • struggle to say words or sentences
  • not understand words that are being used, or the instructions they hear
  • have difficulties knowing how to talk and listen to others in a conversation.

A child with specific language impairment (SLI) may:

  • have difficulty saying what they want to, even though they have ideas
  • talk in sentences but be difficult to understand
  • sound muddled
  • find it difficult to understand words and long instructions
  • have difficulty finding the words they want to say
  • find it hard to join in and follow what is going on in group situations.

Very often children with SLI have difficulty learning to read and spell. They are also more likely to have behavioural, emotional and social difficulties, mainly relationships with other children and emotional difficulties, and to a lesser extent conduct problems.

What are the causes?

Children might have SLCN for a whole range of reasons. For example it may be associated with a learning difficulty or physical difficulty. 

SLI fits under the broad heading of SLCN, but these children have very specific difficulties with language. They don’t have any underlying syndrome or physical problem that may make it difficult to learn how to communicate.

How is it diagnosed?

Significant SLCN will be apparent in the preschool period with identification by around age 2 years plus. Diagnosis may be by a speech and language therapist (SLT), but often the first person parents will contact will be the GP or early years’ staff if the child is attending early years provision. A community paediatrician may also be involved. Parents may be able to self refer for assessment of their child’s speech and language needs.

How is it treated?

Speech and language therapy is given to children and young people to enable them to reach their potential in terms of speech, language and communication. Speech and language therapy should be delivered by a trained SLT. Education staff are also important, both in early years settings and schools, because addressing language difficulties also requires educational interventions. Ideally, SLTs and education staff should work collaboratively as their different expertise is complementary.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
Patterns of inheritance for SLI are not known. Patterns of inheritance for secondary speech and/or language impairment will be based on the inheritance of that particular condition. Affected families should be referred to a genetics service for further support and information.

Prenatal diagnosis
This will be possible when the secondary difficulty is associated with a specific disorder for which prenatal diagnosis has been developed.

Is there support?


Helpline: 0300 666 9410
Email: via website
Website: afasic.org.uk

The Organisation is a Registered Charity in England and Wales No. 1045617. It provides information, support and training for parents of children and young people with speech and language impairments. Members meet in local groups in many areas of the UK.

Group details last reviewed May 2023.

Speech and Language UK

Tel: 020 7843 2510
Email: info@speechandlanguage.org.uk
Website: speechandlanguage.org.uk

Speech and Language UK is a registered charity in England and Wales No. 210031. THey support children from 0-19 through their Talk programmes and two specialist schools. They provide resources and information for parents, families and people who work with children and young people through their Enquiry Service. Speech and Language UK work in nurseries and schools across the UK with evidence-based programmes and run two special schools for children with the most severe and complex needs. 

Group details last updated May 2023.

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