Secondary professions for a Ranger

Ranger/Warrior

 * Rampage as One combined with skills from the line of Hammer Mastery, provides quick adrenaline gain. These rangers are often referred to as "Bunny-Thumpers".
 * Many energy consuming Warrior Skills like Thrill of Victory and Soldier's Strike can be effiecently spammed through Expertise as well as the Rangers considerably higher energy pools and regen time. Such builds can be devastating when combined with Stances such as Lightning Reflexes and Whirling Defense
 * Many of the Warrior's attack speed increasing abilites can provide higher DPS and with the Ranger's safe distance from the enemy, skills like Frenzy can allow the Ranger to constantly rapid-fire when using a Shortbow or Flatbow

Ranger/Monk

 * Judge's Insight can provide a considerable damage boost for Barrage, however the combo is too expensive to sustain.
 * Mending Touch is useful for condition removal and Purge Signet is useful for multi-hex removal.
 * Rangers have efficient self heals, and should not invest in Healing Prayers.
 * Resurrection skills such as Rebirth are useful on primary rangers, as they tend to have better survivability than other professions and can save a party from a near Party-wipe.

Ranger/Necromancer

 * The "Touch Ranger" takes advantage of Expertise's effect on touch-range skills. This combined with ranger defensive stances and speed boosts make a powerful build with decent armor ignoring damage and potent healing.

Ranger/Mesmer

 * Echo chains can be useful when trapping.
 * Fevered Dreams can be used to spread AoE conditions.

Ranger/Elementalist

 * Elementalist spells like Conjure Flame can be combined with Barrage to deal extra damage.

Ranger/Assassin

 * Signet of Malice is an effective condition removal skill.
 * Expertise assassins are quite rare as they are not very effective but some have been found effective. Those that do exist, often use the skill Repeating Strike.
 * Using Defensive Stances (ex. Escape) and combining Dagger Attacks can provide the R/A with potent damage dealing as well as superior protection from physical attacks.

Ranger/Ritualist

 * Weapon Spells such as Splinter Weapon, Nightmare Weapon and Brutal Weapon can work well with a bow. They combine with Barrage and Dual Shot to create a potent damage spike.
 * Binding Rituals are affected by expertise, though Primary Ritualist's are often better Spirit Spammers.
 * Draw Spirit or Summon Spirits can be used to move spirits, and require no attribute investment.
 * The Ritualist's reusable resurrection skills are useful on a primary Ranger in PvE due to the profession's high survivability, although generally not as useful as Rebirth.
 * Combining Ritualist and Ranger Spirits can be useful but Ranger's lack of Spawning Power make it difficult for a spammer to keep them alive.

Ranger/Paragon

 * Spear attacks are affected by Expertise, thus allowing a ranger to spam them.
 * Paragon Shouts like Anthem of Envy can provide great spiking boosts when combined with Barrage

Ranger/Dervish

 * Rangers can successfully use this build to create a new form of condition dealing. By using the elite Ebon Dust Aura on a ebon bow, in addition to the other condition causing enchantments the dervish has to offer, this ranger has the ability to cause serious damage and provide successful defense against warriors and assassins.
 * Heart of Holy Flame and Barrage are useful against undead foes.