A/HRC/31/58 impunity. Concurrently, significant gaps remain in the implementation of the legal standards and the sharing of information leading to an inadequate law enforcement response. 79. A definitive understanding of offenders still needs to be achieved. The existing profiles, such as the distinction between preferential and situational offenders, remains open to debate. There is also scarce and conflicting information about online offenders and female offenders. Further research is consequently necessary with clear parameters to ensure comprehensive and evidence-based results. The inconclusive results of rehabilitation programmes are also linked to the incomplete knowledge about the different types of offenders. The effectiveness of the programmes will thus be improved once those gaps have been filled. 80. In 2016, it will be 20 years since the first World Congress against Commercial Sexual Exploitation of Children was held in Stockholm. Substantial commitments were made by several stakeholders in the declarations at the end of that Congress and the following two, which were held in Yokohama, Japan, in 2001 and in Rio de Janeiro, Brazil, in 2008. The Special Rapporteur hopes that the anniversary will be an opportunity to look back at the progress that has been achieved and focus specifically on the pledges that were made in respect to demand in the Rio de Janeiro Declaration and Call for Action to Prevent and Stop Sexual Exploitation of Children and Adolescents. B. Recommendations 81. In order to eradicate the sexual exploitation of children, it is critical for States and all stakeholders to focus on the demand factor and establish comprehensive strategies to reduce it effectively. The Special Rapporteur recommends the adoption of the following measures. 1. At the national level 82. The Special Rapporteur invites all States to: (a) Ratify all relevant regional and international instruments, in particular the Optional Protocol to the Convention on the Rights of the Child on the sale of children, child prostitution and child pornography, and establish clear and comprehensive legal frameworks by adopting or reforming laws to explicitly prohibit and criminalize all forms of sale and sexual exploitation; (b) Ensure that legal frameworks specifically address the demand for child sexual exploitation by providing clear guidance on penalties that are commensurate with the gravity of the offence; (c) Ensure that criminal proceedings against offenders can always be initiated ex officio; (d) Pay particular attention to the prosecution and conviction of all intermediaries, such as procurers, traffickers and facilitators in the tourism and entertainment industries, as well as financial and technology sector staff, at every level of the supply chain in order to effectively stem the sexual exploitation of children; (e) Ensure that all the proceeds and assets derived from the sexual exploitation of children are effectively seized and confiscated in order to fund care, recovery and reintegration programmes, which should include compensatory measures for the victims; 20