Diane Pretty hopes to make legal history
The DPP has not ruled out the possibility of Mr Pretty being charged with the criminal offence of aiding and abetting a suicide under the Suicide Act 1961. Previously, the act of suicide itself and attempted suicide was also a crime.
Aiding and abetting a suicide potentially carries a maximum sentence of 14 years in prison.
The judges said that their verdict was "inescapable", which was why they refused Mrs Pretty the right to appeal against the decision.
However, this is certainly not the end of the matter.
However, she has been given leave to appeal to the House of Lords.
If she fails there, she could move into Europe, heading for the European Court of Human Rights in Strasbourg.
However, a crucial factor in Diane Pretty's case is the amount of time it would take to prepare for each stage of this legal process.
Mrs Pretty is already at an advanced stage of motor neurone disease, which progressively robs her of the ability to control her muscles.
She is already paralysed from the neck down, and has difficulty speaking clearly.
The 42-year-old was only able to attend the High Court for short periods because of her illness.
The progress of the disease to affect the muscles which control breathing will eventually lead to her death.
While an appeal to the Law Lords could be heard relatively swiftly, preparations for a challenge in the European Courts could take considerably longer.
Supporters have described her as "a tough lady", but it remains to be seen how much further in the legal process she can go.
Certainly, her supporters such as the civil rights charity Liberty have made it clear that they are prepared to support the legal case to the House of Lords and beyond.
Legal position
The judges have now ruled against every separate legal challenge in her case.
She had argued that the Director of Public Prosecutions should have given an undertaking not to prosecute her husband should he help her commit suicide.
Ultimately, the discretion lies with the DPP whether to bring proceedings, but he also has to take public interest into account.
In this case, the DPP said that no undertaking could be given because it would be like issuing a pardon for a crime which had not yet been committed.
Lord Justice Tuckey said: "As the DPP has no power to give the undertaking sought, we cannot give Mrs Pretty the remedy for which she has asked."
Mrs Pretty has also argued that her rights, guaranteed under the Human Rights Act 1998, are being violated.
In particular she is arguing that being required to go on living in the advanced stages of motor neurone disease is subjecting her to ill treatment contrary to Article 3 of this act.
Article 3 states that: "No one shall be subjected to torture or inhumane or degrading treatment or punishment".
Lord Justice Tuckey said: "Whatever the strength of the human rights arguments advanced, they could not properly be used to compel the DPP to act in this way."
He added: "This case concerns the conflict between two of the fundamental rights possessed by all human beings: the right to life and the right to decide what will and will not be done with one's own body."
Mrs Pretty's lawyers had also advanced the argument that the right to dignity enshrined in human rights legislation meant that she should be allowed to die with dignity.
However, the judges said that this argument turned the entire purpose of the legislation on its head. Lord Justice Tuckey said that the rights were intended to protect the fundamental value of life itself.