The appeal in this case follows denial by the trial court of the father’s request for an Order awarding him shared physical custody of his son.
Anthony Agati, the only child of the parties, was born in 1979 and was four years old at the time of the hearing. The parties are divorced, having married in 1978. In August, 1981, Judge Patrick Toole entered a custody and partial custody Order from which no appeal was taken. Subsequently, the parties, by agreement, modified and extended that Order to accommodate their work schedules and to increase the father’s weekend partial custody to include *135Friday nights on alternate weekends and for alternating holidays (T.T. 34a). The father filed a Petition for Visitation 1 which requested an extensive increase in partial custody, in effect, to obtain shared custody as permitted under the Custody and Grandparents Visitation Act, 23 P.S. § 1001 et seq.
Following a hearing before a master to mediate the dispute on April 28, 1983, the case was appealed to the Common Pleas Court and the matter came to hearing before Judge Chester B. Muroski on October 3, 1983. By consent of the parties, the hearing incorporated without petition, consideration of the request of the paternal grandparents for separate partial custody. Following the hearing, during which an adequate record was made, an Order was expeditiously filed on October 4, 1983, from which this appeal was taken. An Opinion was filed by the trial judge, which in a comprehensive and careful manner, considered all issues raised. Lewis v. Lewis, 267 Pa.Super. 235, 406 A.2d 781 (1979).
Our scope of review in custody modification matters is governed by the law as it relates to initial custody hearings. The scope of appellate review in a custody matter is of the broadest type. An appellate court is empowered to determine whether the trial court’s incontrovertible factual findings support the trial court’s conclusions, but may not interfere with those conclusions unless they are unreasonable in light of the trial court’s factual findings, and thus represent a gross abuse of discretion. Commonwealth ex rel. Robinson v. Robinson, 505 Pa. 226, 478 A.2d 800, 806 (1984); Commonwealth ex rel. Spriggs v. Carson, 470 Pa. 290, 368 A.2d 635 (1977).
The major issue in this case, as presented by the appellant, is whether a substantial change of circumstance is the legal standard to apply when a petition is heard for modification of a partial custody Order. Appellant argues it is *136not and would apply the best interest standard negating the need by the petitioner to prove a change of circumstance before reaching the merits of the case. We disagree.
At the outset, prior to the existence of a custody Order, the parties who are parents stand on an equal footing and the only burden carried by either of them is to establish what is in the best interest of the child. In re Custody of Hernandez, 249 Pa.Super. 274, 376 A.2d 648 (1977); Spriggs v. Carson, supra.
It is tempting to modify a partial custody Order on the best interest of the child without first establishing a substantial change in circumstance. This would, however, be extremely destabilizing and could result in spurious petitions based on temporary or vacillating circumstances or a frequent relitigation of issues once resolved. One of the attributes of custody Orders is their temporariness and lack of finality, but change without careful discretion turn the courts into instruments of destruction. Virtually every custody Order also becomes a partial custody Order and while a modification of a custody Order (to bring about an absolute change in custody) requires a change in circumstance which imports some finality, the appellant would subject partial custody to constant tribulation when someone’s perceived best interest test would be suggested, without first being required to show a change of circumstance. The question presents itself as to how one can, at the same time, maintain a change of circumstance standard for a total change of custody while permitting a review of partial custody on a best interest standard. Immediately presented is the additional problem of burden of proof. See In re Custody of Hernandez, supra. In Spriggs v. Carson, supra, the burden of proof as to best interest is equally apportioned between parents; would we now require that this concept be confused by requiring the party alleging best interest for modification of partial custody, carry the burden of proof as he would be required to carry the burden of establishing a change of circumstance? If the petitioners carried no burden in moving directly to consider*137ation of best interest without proof of change of circumstance, would it not be possible to change the custodial parent when it seemed in the best interest of the child to do so? In doing so, the requirement to establish change of circumstance for a total change of custody could be circumvented by petitioning for modification of partial custody. In various contexts, with the exception of the initial custody proceeding between parents, preliminary burdens of proof must be met before best interest can be considered. See In the Interest of LaRue, 244 Pa.Super. 218, 366 A.2d 1271 (1976); Matter of DeSavage, 241 Pa.Super. 174, 360 A.2d 237 (1976); In re Rose, 161 Pa.Super. 204, 54 A.2d 297 (1947).2 It would appear that we would be moving to a doctrine wherein best interest would control, regardless of whether the contest was between parents, as it would be difficult not to justify the same standard as it applied to parents and third parties. See Spriggs v. Carson, supra (Dissent by Justice Flaherty). It is probably illusory that a best interest test will produce any fairer result than the change of circumstances standard. Any change of circumstance which would result in a modification of the Order must also be in the best interest of the child and the court must so find. Once a full and comprehensive review of the case was had, and decision rendered awarding custody and partial custody, it must be assumed that to the degree possible, the best interest of the child was served. In practice, while the best interest standard purportedly governs the decisions in custody cases, as between co-equals, the line is so thin as to be virtually nonexistent thus subject to endless reinterpretation and reargument. Witness the result condemned by the Supreme Court in Robinson, supra, when this Court adopted an independent scope of review. If a request was made for a change in partial custody because of the best interest of the child, this could not be accomplished without doing harm to the doctrine of res judicata, permanency of decisions, and stability of the child, unless a sufficient change of circumstance was estab*138lished to warrant a modification, as the then best interest no longer applies. Change of circumstance is still the standard, which necessarily encompasses a consideration of the child’s best interest. If it is truly in the best interest of the child to modify a partial custody order, it would be unlikely that there would be a lack of proof of change of circumstance.
An additional complicating factor which moves us to a more rigid compliance to the change of circumstance standard is the advent of the Uniform Child Custody Jurisdiction Act, 42 Pa.C.S. § 5341 et seq. See Commonwealth ex rel. Zaubi v. Zaubi, 275 Pa.Super. 294, 418 A.2d 729 (1980). The perplexing problem of child snatching and forum shopping required national cooperation to give some finality to custody Orders and a determined application of the change of circumstance requirement to avoid defeating the intent of the U.C.C.J.A.
Except in an initial custody action, best interest is generally the second consideration, there being an evidentiary gate which must be passed before it can be considered. Making best interest the gate instead of the support for custody decisions predisposes to irrational and/or untenable decisions. See LaRue, DeSavage, Rose, supra.
Some states have relied on section 407(b) [Visitation] of the Uniform Marriage and Divorce Act (UMDA) (1973) for introducing a new relaxed standard of best interest when modification of a partial custody Order is required.3 This may well be a misinterpretation of that section as it relates to the act as a whole.
The UMDA section 407(b) on Visitation simply articulated the traditional rule that visitation was presumed to be in the best interest of the child, and that standard would apply in granting visitation, although an extraordinary standard of “ ‘seriously (endangering) the child’s physical, mental, and moral, or emotional health would apply in denying *139visitation’ ” (Commissioner’s notes). It does not appear that it was meant to be a different standard than applied in section 409 (Modification) which contains a change of circumstance and a best interest standard for modification. All sections of the UMDA must be read together and where possible consistent with each other. It would be untenable to find that a visitation or partial custody Order could be modified without also modifying the underlying custody Order. To the degree one adds or subtracts from the time and circumstances of a custody degree to enhance or restrict visitation or partial custody, it is a modification of the custody Order. The salient point is made by section 409(a), Modification, “No motion to modify a custody decree may be made earlier than 2 years after its date, unless the court permits it be made on the basis of affidavits that there is reason to believe the child’s present environment may endanger seriously his physical, mental, moral, or emotional health.” 4
While this appears clearly to speak primarily to custody it must speak with equal force to visitation and partial custody as the effect of either the custodial or noncustodial environment is a critical consideration in custody and would subject the case to review under proper circumstances. While the UMDA makes no distinction between visitation and partial custody, Pennsylvania case law and rules make a very clear distinction. Pa.R.C.P. 1915.1(b) defines partial custody and visitation as follows:
Rule 1915.1(b) Scope. Definitions
‘partial custody’ means the right to take possession of a child away from the custodial person for a certain period of time;
‘visitation’ means the right to visit a child, but does not include the right to remove the child from the custodial person’s control.
*140This distinction is important as the UMDA does not spell out the difference between visitation and partial custody, thus we cannot be certain that they are considered the same and that the same standard of review would be applicable to both. It is far easier to advocate a relaxed standard for modifying a ‘visitation’ Order as opposed to a ‘partial custody’ Order.
With new concepts gaining vogue in custody cases, shared custody, joint custody and partial custody become a continuum with sole custody, upon which a decision is based. The line of demarcation becomes extremely blurred and it becomes increasingly difficult to determine, as between the two parents, who is the de facto custodian, especially when “shared custody” pursuant to Pa.R.C.P. 1915.1(b) is imposed. “Shared custody” means shared legal or shared physical custody or both of a child in such a way as to assure the child of frequent and continuing contact, including physical access, to both parents.
The “commissioner’s notes” following section 409 point out,
Most experts who have spoken to the problems of post-divorce adjustment of children, believe that insuring the decree’s finality is more important than determining which parent should be custodian. See Watson, The Children of Armageddon: Problems of Custody Following Divorce, 21 Syracuse L.Rev. 55 (1969). This section is designed to maximize finality (and thus assure continuity for the child) without jeopardizing the child’s interest.
In a renowned broadly publicized work, J. Goldstein, A. Freud and A. Solnit, Beyond the Best Interest of the Child, 97-101 (1973), the authors propose provisions for a child placement code and would deny visitation (partial custody) entirely. At Para. 30.5, Final Unconditional Disposal,
All placements shall be unconditional and final, that is, the court shall not retain continuing jurisdiction over a parent-child relationship or establish or enforce such conditions as rights of visitation.
*141This proposal is obviously inappropriate to our philosophy and legal tradition. It does point out, however, the consequence of carrying the concept of best interest, to its ultimate conclusion, i.e. placing stability of the child (best interest) beyond any rights of parents.
Our rules make no distinction between full custody hearings and subsequent modification hearings, nor do they provide for a different procedure for visitation and partial custody as opposed to custody. To impose a new and different standard of review for partial custody would simply increase the vexation and the likelihood of rehearing, make less certain the appropriateness of a decision and assure a greater probability of chronic litigation. Nothing disturbs the child’s perception of stability and harmony more than frequent litigation concerning him by his parents.
The need to establish change of circumstance in a modification hearing was reaffirmed by Daniel K.D. v. Jan M.H., 301 Pa.Super. 36, 446 A.2d 1323 (1982), which stated, “Under current case law, (the) party seeking modification of (a) custody award continues to have (the) burden of proving (a) substantial change in circumstances which will justify (the) court’s reconsideration of (the) extant custody award,____” In footnote 2, 301 Pa.Superior Ct. at 40, 446 A.2d at 1324, the court quoted:
‘To permit a party to relitigate a subject of relative fitness of parents to have custody of children by an inquiry into the same or other facts existing at the time of or prior to the former decree would lay a foundation for interminable and vexatious litigation____’ Commonwealth ex rel. O’Hey v. McCurdy, 199 Pa.Super.Ct. 22, 24, 184 A.2d 290, 291 (1962) (quoting Commonwealth ex rel. Crawford v. Crawford, 170 Pa.Super.Ct. 151, 154, 84 A.2d 237, 238 (1951) (further citations omitted).
For this reason as well as others cited above, the clear requirement of change of circumstance prior to application of best interest is necessary to avoid the uncertainty and instability that a best interest test alone would provide. *142This is not the only time that a prior standard is required before looking to best interest, Rose, supra (a finding of dependency must be made before best interest can be considered), La Rue, supra (removal of a child from its home requires a. finding of clear necessity rather than best interest). The change of circumstance requirement places the courts review of partial custody matters between the best interest standard espoused by the appellant and the denial of any review proposed by Beyond the Best Interest of the Child, supra. Here, the review was sought within one and one-half years of the original custody Order based primarily on the passage of time for a child who went from two and one-half to four years of age.
In this case, the matter would have been resolved more expeditiously and without injustice if dismissed on the basis of failure to show a change of circumstance. However, the court did incorporate into the Order the increased periods of partial custody the parents themselves had worked out since the prior Order. This we approve since to a great extent the most satisfactory custody Orders are those in which the parents have worked out a reasonable accommodation. The court correctly determined on the facts that there were no changes of circumstance proven since the Order of August 13, 1983. It further determined that the case did not warrant consideration of expanded shared custody, which was an unnecessary finding in view of the prior one. We will not consider it further.
The one remaining issue relates to the oral request, acceded to by the parties, to consider independent partial custody for the paternal grandparents.
The court found that the grandparents enjoy a regular, meaningful and significant relationship with their grandchild and frequently the overnight visits to the father have been spent at the home of the grandparents. In order to increase the grandparents time, it would be necessary to subtract from that of the mother. The lower court took into consideration the de facto arrangement worked out by *143the father and his parents, and incorporated into the Order a direction that “one of the weekday periods for partial custody be a period in which the grandparents would be entitled to a period of partial custody as selected by the father and with his consent.” This fulfills the requirements of the Custody and Grandparents Visitation Act, supra, and appears to be in the child’s best interest. Commonwealth ex rel. Zaffarano v. Genaro, 286 Pa.Super. 436, 429 A.2d 17 (1981).
The Order of the court below is affirmed.
BECK, J., files a concurring opinion.. In reality, a Petition to Extend Partial Custody to include Shared Custody. See Actions for Custody, Partial Custody and Visitation of Minor Children, Pa.R.C.P. 1915.1 et seq.
. Child’s dependency must be established before the court can consider best interest.
. Arizona, Colorado, Illinois, Kentucky, Minnesota, Missouri, Montana and Washington are among those states.
. Kentucky has adopted section 409(a). See S. v. S., 7 F.L.R. 2132 (1980).