Genetic testing for cystic fibrosis (CF) has evolved, with a distinction between "full CFTR sequencing" and comprehensive sequencing of the coding and flanking regions. Comprehensive sequencing, which includes all exons and intronic regions, is now recommended for patients with CF-related meconium-stained stools (pwCRMS) who do not have two identified causal CFTR variants after newborn screening (NBS). This test is widely available and can identify additional variants, providing better prognostic information and risk estimates for parents. Next-generation sequencing (NGS) is commonly used for this purpose, though it may not detect large structural variants like exon deletions or duplications. Some laboratories offer separate analysis for these variants. A new recommendation is to offer additional CFTR testing that sequences all coding and noncoding regions, including introns, upstream, and downstream sequences. This is particularly relevant for infants with one identified CFTR variant and a high suspicion of CF, such as those with elevated sweat chloride levels. The extent of testing should be considered, as the detection rate may not increase significantly if only a small number of intronic regions are sequenced. Communicating the diagnosis of cystic fibrosis-related meconium-stained stools (CRMS/CFSPID) is challenging. Individualized written information and genetic counseling can improve understanding. A 4-step model for communicating diagnostic uncertainty and follow-up educational sessions can enhance communication. Educational tools and teach-back techniques are effective in ensuring understanding. Genetic counseling at regular intervals provides timely and supportive information on recurrence risk and reproductive options. The Cystic Fibrosis Foundation (CFF) developed consensus guidelines with a multidisciplinary team, including physicians, genetic counselors, and parents. The team conducted literature searches and developed draft recommendations. The committee reviewed and revised these recommendations, incorporating public feedback. The final manuscript was approved by the committee before submission for publication.Genetic testing for cystic fibrosis (CF) has evolved, with a distinction between "full CFTR sequencing" and comprehensive sequencing of the coding and flanking regions. Comprehensive sequencing, which includes all exons and intronic regions, is now recommended for patients with CF-related meconium-stained stools (pwCRMS) who do not have two identified causal CFTR variants after newborn screening (NBS). This test is widely available and can identify additional variants, providing better prognostic information and risk estimates for parents. Next-generation sequencing (NGS) is commonly used for this purpose, though it may not detect large structural variants like exon deletions or duplications. Some laboratories offer separate analysis for these variants. A new recommendation is to offer additional CFTR testing that sequences all coding and noncoding regions, including introns, upstream, and downstream sequences. This is particularly relevant for infants with one identified CFTR variant and a high suspicion of CF, such as those with elevated sweat chloride levels. The extent of testing should be considered, as the detection rate may not increase significantly if only a small number of intronic regions are sequenced. Communicating the diagnosis of cystic fibrosis-related meconium-stained stools (CRMS/CFSPID) is challenging. Individualized written information and genetic counseling can improve understanding. A 4-step model for communicating diagnostic uncertainty and follow-up educational sessions can enhance communication. Educational tools and teach-back techniques are effective in ensuring understanding. Genetic counseling at regular intervals provides timely and supportive information on recurrence risk and reproductive options. The Cystic Fibrosis Foundation (CFF) developed consensus guidelines with a multidisciplinary team, including physicians, genetic counselors, and parents. The team conducted literature searches and developed draft recommendations. The committee reviewed and revised these recommendations, incorporating public feedback. The final manuscript was approved by the committee before submission for publication.