“So, what is spiritual direction?”
At times, the easiest way to answer this question is to say what spiritual direction is not. A spiritual director is not a counselor or psychotherapist, not a life coach or personal trainer, not an accountability or prayer partner, not a pastor, and not the same for every person. Spiritual direction is not pushy, and not even very directive!
So, what is spiritual direction? Spiritual direction is an ancient Christian practice that is very effective for spiritual growth. Generally, the director and directee meet monthly for about an hour. 
According to the Mennonite Spiritual Directors Association, “Fundamentally a ministry of prayer, spiritual direction is a one-with-one relationship in which directors accompany others on their journey to mature faith in Christ.” Key words here are “prayer,” “relationship,” “accompany,” and “Christ.” Spiritual direction is helping another person fulfill their desire to really know our triune God. All else is “loss” in comparison to “knowing Christ” (Phil 3:8).
According to the Evangelical Spiritual Directors Association: “Spiritual direction is a safe place to explore your questions and concerns about your life with God. A Christian spiritual director is a trained listener who will accompany you as you share about your spiritual journey, helping you notice God’s presence and activity along the way, as well as your personal reactions and responses. Hospitable, confidential, and grounded in biblical truth, spiritual direction is a ministry that helps you grow in prayer and live into your calling as a follower of Christ.” Key words here are “trained listener,” “your life with God,” “notice” and “hospitable.” 
Good spiritual directors are not trying to instill their own theology but to create a hospitable listening space in which God patiently, lovingly, persistently forms you to be all He specifically and carefully designed you to be (Ps 139).
God is always communicating with us. The spiritual director helps the directee hear, see, feel and recognize our self-revealing God. As we see how God is already active in our lives, our relationship with Him deepens; we see all of life more clearly; and we get glimpses of how to follow Him and how to allow Him to love us. The personal relationship with Jesus of which we have heard so much and the abiding and passionate love for God we have always desired finally come to life.
For Christian spiritual directors, Jesus is central to all of life. This unchanging foundation will come out as they do spiritual direction, particularly in faith that God is self-giving, good, holy, unchanging, and untiringly communicating with the directee. However, there is much freedom in direction because there is much, much trust in God alone as the Director. This freedom shows up in multiple ways. For example, directees may be offered options of ways to pray, but directors do not “check up” to see if they did it.
Spiritual directors trust that directees will continue to move toward God (as much as they are able, often in fits and starts) as God is speaking and inviting them. It is not a director’s job to make that happen, just to accompany, support and cheer the process. 
However, it is a spiritual director’s job to be a careful and care-full listener and to pray often for their directees.
So, who would benefit from going to a spiritual director? Oh, that answer is much easier…Anyone who wants to grow in relationship with God! Spiritual direction is particularly helpful at times of transition, for discernment and decision-making. However, meeting with a spiritual director is also an opportunity to see God at work, reflect on life experiences, understand oneself better, explore hopes and dreams, and especially to offer time and hold open space to hear God’s voice.
Pastors, priests, and ministers often benefit from spiritual direction because they are so prone to busyness, resulting in spiritual exhaustion and neglect of their prayer life. 
Spiritual direction provides them a safe, confidential place to ask God questions and a pause for listening to God’s answers. However, new believers and seekers also encounter God again and again as they turn their minds and hearts to find Him. Our God desires to be found.
Starting spiritual direction can be a frightening endeavor, as can any decision to really know God. A lot of courage is required to intentionally invite God to enter and indwell us—mind, heart, spirit, and body. We experience an unsettled feeling, wondering what in the world this holy yet forgiving, unmanageable yet attentive, huge but tender, unfathomable yet fatherly God has in mind for us. However, in taking the risk to know God better, we learn new ways to “Be still and know that I am God” (Ps 46:10) and to join with the Apostle Paul in declaring, “For me, to live is Christ” (Phil 1:21). We experience afresh God as our refuge and strength and the lover of our souls.
So, what is spiritual direction? Perhaps the best answer to this question is found by responding to the invitation Jesus so often gives us, to “come and see.”