Treating phonological delays is nothing new for most speech-language pathologists. We can easily identify stopping, fronting, gliding, cluster reduction and depalatisation and we know how to use the minimal pairs approach, the complexity approach, the cycles approach and multiple oppositions approach. However, what happens when we encounter atypical phonological processes? In part one we looked at what atypical phonological processes are – errors like backing, initial consonant deletion, gliding of fricatives and nasalisation, which fall outside the typical developmental patterns – and how to assess for them accurately, ruling out assimilation, dialect influence and inconsistent phonological disorder along the way.
Once you have accurately identified atypical phonological errors, the treatment approach diverges meaningfully from what you might use for a typical phonological delay. Here is what the evidence supports.
Start Treatment Immediately
There is no role for ‘watchful waiting’ when atypical phonological errors are present. Research by Roepke et al. (2026) found that when compared to children with typical phonological errors, children who produce atypical phonological errors have significantly more difficulty with phonological awareness, literacy, executive function and they are also more likely to have persistent errors that do not resolve without targeted intervention. This means that a child with atypical phonological errors is not simply a child who will “catch up.” The watch-and-wait approach, which might be appropriate in some cases of mild phonological delay, is not appropriate here. Early, accurate identification and prompt treatment are essential.
Use Minimal Pairs
Minimal pairs therapy is well-supported for atypical phonological errors. When selecting targets, prioritise the atypical patterns that impact the child’s intelligibility the most, and that the child is stimulable for. Stimulability combined with functional impact is your strongest starting point for target selection.
Focus on Contrast, Not Complexity
The complexity approach operates on the principle that teaching more phonologically complex structures will result in generalisation to less complex structures. However, this logic does not transfer well to atypical phonological errors. Many children with atypical errors are already producing complex structures – they are just producing them in the wrong place. Backing of alveolar sounds (e.g., table → cable) and affrication of fricatives (e.g., shark → chark) are both examples of complex productions occurring where simpler ones are expected. For these children, the focus should be on contrast, not on increasing phonological complexity.
Always Assess and Target Phonological Awareness
Phonological awareness assessment and intervention should be a non-negotiable component of treatment for any child with atypical phonological errors. Phonological processing deficits can persist even after speech production has significantly improved – meaning a child may be highly intelligible but still be at risk for literacy difficulties if phonological awareness is not explicitly targeted. Importantly, you should take the child’s speech errors into consideration when completing phonological awareness tasks, e.g. if a child glides all their fricatives, you should avoid words containing /s/, /z/, /sh/, /zh/, /f/ & /v/.
Address Inconsistency First
If your assessment has identified inconsistent phonological disorder alongside atypical errors, whole-word consistency must be established before targeting phonological patterns. The core vocabulary approach is the treatment of choice here. Select 50 high-impact, functionally important words. Target 10 words per week, teaching each word sound-by-sound to establish a stable, consistent production. Once the child’s speech demonstrates greater consistency, transition to a contrast-based approach to address the underlying phonological system.
Treat Phoneme Collapse with Multiple Oppositions
Phoneme collapse – also called sound preference substitution – is when a child replaces an entire group of consonants with a single sound. While this falls under the broader category of atypical phonological errors, it is treated differently from other atypical patterns. Multiple oppositions therapy is the approach of choice for phoneme collapse. This approach simultaneously contrasts multiple target sounds against the child’s error sound, directly addressing the collapsed system and helping the child differentiate between sounds that have become functionally merged.
Rethink How You Measure Progress
Percent consonants correct (PCC) is a well-established measure for phonological disorders broadly, but it may not tell the full story for children with atypical errors. A child can make clinically meaningful gains in intelligibility that PCC does not adequately capture. Consider measuring intelligibility in context over time as a more valid indicator of progress. Tools like the SPAA-C (Speech Participation and Activity Assessment of Children) provide a broader picture of the real-world impact of the disorder and how it is changing with intervention.
Address Morphosyntax if DLD Is Also Present
For children with co-occurring developmental language disorder (DLD), phonology cannot be treated in isolation. The current evidence supports alternating between phonology and morphosyntax intervention on a weekly basis. When working on phonology, incorporate phonological awareness. When working on language, use language-based strategies – such as recasting – to consistently provide strong phonological and language models. This integrated approach ensures that neither system is neglected and that intervention reflects the complexity of the child’s full profile.
Putting It All Together
Atypical phonological processes are not simply a more severe version of typical phonological delay. They are a clinically distinct presentation with distinct risk factors, distinct assessment requirements, and distinct treatment pathways. The children who present with these errors are at elevated risk for literacy difficulties and persistent speech errors – which means the clinical decisions we make early on carry real weight.
The good news is that the evidence base is clear and growing. We know what to look for, we know how to assess accurately, and we have effective tools for treatment. The most important thing we can do as clinicians is to resist the pull toward familiar frameworks when the presentation in front of us is asking for something different.
